<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2024 Workiva-->
<!--r:eff9a1dc-bcb9-426a-a2f4-8d5eed2da10b,g:9e4fbd4e-5552-4277-8b32-f6e03db27853-->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:aos="http://www.aosmith.com/20231231" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:dtr-types1="http://www.xbrl.org/dtr/type/2020-01-21" xmlns:dtr-types="http://www.xbrl.org/dtr/type/2022-03-31" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" attributeFormDefault="unqualified" elementFormDefault="qualified" targetNamespace="http://www.aosmith.com/20231231">
  <xs:import namespace="http://fasb.org/srt/2023" schemaLocation="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd"/>
  <xs:import namespace="http://fasb.org/us-gaap/2023" schemaLocation="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd"/>
  <xs:import namespace="http://www.w3.org/1999/xlink" schemaLocation="http://www.xbrl.org/2003/xlink-2003-12-31.xsd"/>
  <xs:import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd"/>
  <xs:import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd"/>
  <xs:import namespace="http://www.xbrl.org/dtr/type/2020-01-21" schemaLocation="https://www.xbrl.org/dtr/type/2020-01-21/types.xsd"/>
  <xs:import namespace="http://www.xbrl.org/dtr/type/2022-03-31" schemaLocation="https://www.xbrl.org/dtr/type/2022-03-31/types.xsd"/>
  <xs:import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd"/>
  <xs:import namespace="http://xbrl.sec.gov/country/2023" schemaLocation="https://xbrl.sec.gov/country/2023/country-2023.xsd"/>
  <xs:import namespace="http://xbrl.sec.gov/currency/2023" schemaLocation="https://xbrl.sec.gov/currency/2023/currency-2023.xsd"/>
  <xs:import namespace="http://xbrl.sec.gov/dei/2023" schemaLocation="https://xbrl.sec.gov/dei/2023/dei-2023.xsd"/>
  <xs:import namespace="http://xbrl.sec.gov/ecd/2023" schemaLocation="https://xbrl.sec.gov/ecd/2023/ecd-2023.xsd"/>
  <xs:annotation>
    <xs:appinfo>
      <link:linkbaseRef xmlns:xlink="http://www.w3.org/1999/xlink" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="aos-20231231_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:type="simple"/>
      <link:linkbaseRef xmlns:xlink="http://www.w3.org/1999/xlink" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="aos-20231231_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:type="simple"/>
      <link:linkbaseRef xmlns:xlink="http://www.w3.org/1999/xlink" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="aos-20231231_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:type="simple"/>
      <link:linkbaseRef xmlns:xlink="http://www.w3.org/1999/xlink" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="aos-20231231_cal.xml" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:type="simple"/>
      <link:roleType id="CoverPage" roleURI="http://www.aosmith.com/role/CoverPage">
        <link:definition>0000001 - Document - Cover Page</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="AuditInformation" roleURI="http://www.aosmith.com/role/AuditInformation">
        <link:definition>0000002 - Document - Audit Information</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CONSOLIDATEDBALANCESHEETS" roleURI="http://www.aosmith.com/role/CONSOLIDATEDBALANCESHEETS">
        <link:definition>0000003 - Statement - CONSOLIDATED BALANCE SHEETS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CONSOLIDATEDBALANCESHEETSParenthetical" roleURI="http://www.aosmith.com/role/CONSOLIDATEDBALANCESHEETSParenthetical">
        <link:definition>0000004 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CONSOLIDATEDSTATEMENTOFEARNINGS" roleURI="http://www.aosmith.com/role/CONSOLIDATEDSTATEMENTOFEARNINGS">
        <link:definition>0000005 - Statement - CONSOLIDATED STATEMENT OF EARNINGS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CONSOLIDATEDSTATEMENTOFCOMPREHENSIVEEARNINGS" roleURI="http://www.aosmith.com/role/CONSOLIDATEDSTATEMENTOFCOMPREHENSIVEEARNINGS">
        <link:definition>0000006 - Statement - CONSOLIDATED STATEMENT OF COMPREHENSIVE EARNINGS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CONSOLIDATEDSTATEMENTOFCOMPREHENSIVEEARNINGSParenthetical" roleURI="http://www.aosmith.com/role/CONSOLIDATEDSTATEMENTOFCOMPREHENSIVEEARNINGSParenthetical">
        <link:definition>0000007 - Statement - CONSOLIDATED STATEMENT OF COMPREHENSIVE EARNINGS (Parenthetical)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CONSOLIDATEDSTATEMENTOFCASHFLOWS" roleURI="http://www.aosmith.com/role/CONSOLIDATEDSTATEMENTOFCASHFLOWS">
        <link:definition>0000008 - Statement - CONSOLIDATED STATEMENT OF CASH FLOWS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CONSOLIDATEDSTATEMENTOFSTOCKHOLDERSEQUITY" roleURI="http://www.aosmith.com/role/CONSOLIDATEDSTATEMENTOFSTOCKHOLDERSEQUITY">
        <link:definition>0000009 - Statement - CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CONSOLIDATEDSTATEMENTOFSTOCKHOLDERSEQUITYParenthetical" roleURI="http://www.aosmith.com/role/CONSOLIDATEDSTATEMENTOFSTOCKHOLDERSEQUITYParenthetical">
        <link:definition>0000010 - Statement - CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY (Parenthetical)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OrganizationandSignificantAccountingPolicies" roleURI="http://www.aosmith.com/role/OrganizationandSignificantAccountingPolicies">
        <link:definition>0000011 - Disclosure - Organization and Significant Accounting Policies</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RevenueRecognition" roleURI="http://www.aosmith.com/role/RevenueRecognition">
        <link:definition>0000012 - Disclosure - Revenue Recognition</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="Acquisitions" roleURI="http://www.aosmith.com/role/Acquisitions">
        <link:definition>0000013 - Disclosure - Acquisitions</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="Leases" roleURI="http://www.aosmith.com/role/Leases">
        <link:definition>0000014 - Disclosure - Leases</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RestructuringandImpairment" roleURI="http://www.aosmith.com/role/RestructuringandImpairment">
        <link:definition>0000015 - Disclosure - Restructuring and Impairment</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StatementofCashFlows" roleURI="http://www.aosmith.com/role/StatementofCashFlows">
        <link:definition>0000016 - Disclosure - Statement of Cash Flows</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="Inventories" roleURI="http://www.aosmith.com/role/Inventories">
        <link:definition>0000017 - Disclosure - Inventories</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PropertyPlantandEquipment" roleURI="http://www.aosmith.com/role/PropertyPlantandEquipment">
        <link:definition>0000018 - Disclosure - Property, Plant and Equipment</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillandOtherIntangibleAssets" roleURI="http://www.aosmith.com/role/GoodwillandOtherIntangibleAssets">
        <link:definition>0000019 - Disclosure - Goodwill and Other Intangible Assets</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="Debt" roleURI="http://www.aosmith.com/role/Debt">
        <link:definition>0000020 - Disclosure - Debt</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockholdersEquity" roleURI="http://www.aosmith.com/role/StockholdersEquity">
        <link:definition>0000021 - Disclosure - Stockholders' Equity</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockBasedCompensation" roleURI="http://www.aosmith.com/role/StockBasedCompensation">
        <link:definition>0000022 - Disclosure - Stock Based Compensation</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PensionandOtherPostretirementBenefits" roleURI="http://www.aosmith.com/role/PensionandOtherPostretirementBenefits">
        <link:definition>0000023 - Disclosure - Pension and Other Post-retirement Benefits</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeInstruments" roleURI="http://www.aosmith.com/role/DerivativeInstruments">
        <link:definition>0000024 - Disclosure - Derivative Instruments</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxes" roleURI="http://www.aosmith.com/role/IncomeTaxes">
        <link:definition>0000025 - Disclosure - Income Taxes</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CommitmentsandContingencies" roleURI="http://www.aosmith.com/role/CommitmentsandContingencies">
        <link:definition>0000026 - Disclosure - Commitments and Contingencies</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OperationsbySegment" roleURI="http://www.aosmith.com/role/OperationsbySegment">
        <link:definition>0000027 - Disclosure - Operations by Segment</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SCHEDULEIIVALUATIONANDQUALIFYINGACCOUNTS" roleURI="http://www.aosmith.com/role/SCHEDULEIIVALUATIONANDQUALIFYINGACCOUNTS">
        <link:definition>0000028 - Disclosure - SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OrganizationandSignificantAccountingPoliciesPolicies" roleURI="http://www.aosmith.com/role/OrganizationandSignificantAccountingPoliciesPolicies">
        <link:definition>9954471 - Disclosure - Organization and Significant Accounting Policies (Policies)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OrganizationandSignificantAccountingPoliciesTables" roleURI="http://www.aosmith.com/role/OrganizationandSignificantAccountingPoliciesTables">
        <link:definition>9954472 - Disclosure - Organization and Significant Accounting Policies (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RevenueRecognitionTables" roleURI="http://www.aosmith.com/role/RevenueRecognitionTables">
        <link:definition>9954473 - Disclosure - Revenue Recognition (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="AcquisitionsTables" roleURI="http://www.aosmith.com/role/AcquisitionsTables">
        <link:definition>9954474 - Disclosure - Acquisitions (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LeasesTables" roleURI="http://www.aosmith.com/role/LeasesTables">
        <link:definition>9954475 - Disclosure - Leases (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StatementofCashFlowsTables" roleURI="http://www.aosmith.com/role/StatementofCashFlowsTables">
        <link:definition>9954476 - Disclosure - Statement of Cash Flows (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="InventoriesTables" roleURI="http://www.aosmith.com/role/InventoriesTables">
        <link:definition>9954477 - Disclosure - Inventories (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PropertyPlantandEquipmentTables" roleURI="http://www.aosmith.com/role/PropertyPlantandEquipmentTables">
        <link:definition>9954478 - Disclosure - Property, Plant and Equipment (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillandOtherIntangibleAssetsTables" roleURI="http://www.aosmith.com/role/GoodwillandOtherIntangibleAssetsTables">
        <link:definition>9954479 - Disclosure - Goodwill and Other Intangible Assets (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DebtTables" roleURI="http://www.aosmith.com/role/DebtTables">
        <link:definition>9954480 - Disclosure - Debt (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockholdersEquityTables" roleURI="http://www.aosmith.com/role/StockholdersEquityTables">
        <link:definition>9954481 - Disclosure - Stockholders' Equity (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockBasedCompensationTables" roleURI="http://www.aosmith.com/role/StockBasedCompensationTables">
        <link:definition>9954482 - Disclosure - Stock Based Compensation (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PensionandOtherPostretirementBenefitsTables" roleURI="http://www.aosmith.com/role/PensionandOtherPostretirementBenefitsTables">
        <link:definition>9954483 - Disclosure - Pension and Other Post-retirement Benefits (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeInstrumentsTables" roleURI="http://www.aosmith.com/role/DerivativeInstrumentsTables">
        <link:definition>9954484 - Disclosure - Derivative Instruments (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesTables" roleURI="http://www.aosmith.com/role/IncomeTaxesTables">
        <link:definition>9954485 - Disclosure - Income Taxes (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OperationsbySegmentTables" roleURI="http://www.aosmith.com/role/OperationsbySegmentTables">
        <link:definition>9954486 - Disclosure - Operations by Segment (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OrganizationandSignificantAccountingPoliciesNarrativeDetails" roleURI="http://www.aosmith.com/role/OrganizationandSignificantAccountingPoliciesNarrativeDetails">
        <link:definition>9954487 - Disclosure - Organization and Significant Accounting Policies - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OrganizationandSignificantAccountingPoliciesCompanysProductWarrantyLiabilityActivityDetails" roleURI="http://www.aosmith.com/role/OrganizationandSignificantAccountingPoliciesCompanysProductWarrantyLiabilityActivityDetails">
        <link:definition>9954488 - Disclosure - Organization and Significant Accounting Policies - Company's Product Warranty Liability Activity (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OrganizationandSignificantAccountingPoliciesAssetsandLiabilitiesMeasuredatFairValueonRecurringBasisDetails" roleURI="http://www.aosmith.com/role/OrganizationandSignificantAccountingPoliciesAssetsandLiabilitiesMeasuredatFairValueonRecurringBasisDetails">
        <link:definition>9954489 - Disclosure - Organization and Significant Accounting Policies - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OrganizationandSignificantAccountingPoliciesScheduleofComputationofBasicandDilutedWeightedAverageSharesUsedinEarningsperShareCalculationsDetails" roleURI="http://www.aosmith.com/role/OrganizationandSignificantAccountingPoliciesScheduleofComputationofBasicandDilutedWeightedAverageSharesUsedinEarningsperShareCalculationsDetails">
        <link:definition>9954490 - Disclosure - Organization and Significant Accounting Policies - Schedule of Computation of Basic and Diluted Weighted-Average Shares Used in Earnings per Share Calculations (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RevenueRecognitionNarrativeDetails" roleURI="http://www.aosmith.com/role/RevenueRecognitionNarrativeDetails">
        <link:definition>9954491 - Disclosure - Revenue Recognition - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RevenueRecognitionSegmentSalesDisaggregatedbyMajorProductLineDetails" roleURI="http://www.aosmith.com/role/RevenueRecognitionSegmentSalesDisaggregatedbyMajorProductLineDetails">
        <link:definition>9954492 - Disclosure - Revenue Recognition - Segment Sales Disaggregated by Major Product Line (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="AcquisitionsNarrativeDetails" roleURI="http://www.aosmith.com/role/AcquisitionsNarrativeDetails">
        <link:definition>9954493 - Disclosure - Acquisitions - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="AcquisitionsSummaryofAllocationofFairValueofAssetsAcquiredandLiabilitiesAssumedatDateofAcquisitionDetails" roleURI="http://www.aosmith.com/role/AcquisitionsSummaryofAllocationofFairValueofAssetsAcquiredandLiabilitiesAssumedatDateofAcquisitionDetails">
        <link:definition>9954494 - Disclosure - Acquisitions - Summary of Allocation of Fair Value of Assets Acquired and Liabilities Assumed at Date of Acquisition (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LeasesNarrativeDetails" roleURI="http://www.aosmith.com/role/LeasesNarrativeDetails">
        <link:definition>9954495 - Disclosure - Leases - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LeasesSupplementalbalancesheetDetails" roleURI="http://www.aosmith.com/role/LeasesSupplementalbalancesheetDetails">
        <link:definition>9954496 - Disclosure - Leases - Supplemental balance sheet (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LeasesComponentsofleaseexpenseDetails" roleURI="http://www.aosmith.com/role/LeasesComponentsofleaseexpenseDetails">
        <link:definition>9954497 - Disclosure - Leases - Components of lease expense (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LeasesMaturitiesofleaseliabilitiesDetails" roleURI="http://www.aosmith.com/role/LeasesMaturitiesofleaseliabilitiesDetails">
        <link:definition>9954498 - Disclosure - Leases - Maturities of lease liabilities (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="LeasesMaturitiesofleaseliabilitiesDetails_1" roleURI="http://www.aosmith.com/role/LeasesMaturitiesofleaseliabilitiesDetails_1">
        <link:definition>9954498 - Disclosure - Leases - Maturities of lease liabilities (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RestructuringandImpairmentNarrativeDetails" roleURI="http://www.aosmith.com/role/RestructuringandImpairmentNarrativeDetails">
        <link:definition>9954499 - Disclosure - Restructuring and Impairment - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StatementofCashFlowsScheduleofSupplementalCashFlowInformationDetails" roleURI="http://www.aosmith.com/role/StatementofCashFlowsScheduleofSupplementalCashFlowInformationDetails">
        <link:definition>9954500 - Disclosure - Statement of Cash Flows - Schedule of Supplemental Cash Flow Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StatementofCashFlowsNarrativeDetails" roleURI="http://www.aosmith.com/role/StatementofCashFlowsNarrativeDetails">
        <link:definition>9954501 - Disclosure - Statement of Cash Flows - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="InventoriesScheduleofInventoriesDetails" roleURI="http://www.aosmith.com/role/InventoriesScheduleofInventoriesDetails">
        <link:definition>9954502 - Disclosure - Inventories - Schedule of Inventories (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PropertyPlantandEquipmentDetails" roleURI="http://www.aosmith.com/role/PropertyPlantandEquipmentDetails">
        <link:definition>9954503 - Disclosure - Property, Plant and Equipment (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillandOtherIntangibleAssetsScheduleofChangesinCarryingAmountofGoodwillDetails" roleURI="http://www.aosmith.com/role/GoodwillandOtherIntangibleAssetsScheduleofChangesinCarryingAmountofGoodwillDetails">
        <link:definition>9954504 - Disclosure - Goodwill and Other Intangible Assets - Schedule of Changes in Carrying Amount of Goodwill (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillandOtherIntangibleAssetsScheduleofCarryingAmountofOtherIntangibleAssetsDetails" roleURI="http://www.aosmith.com/role/GoodwillandOtherIntangibleAssetsScheduleofCarryingAmountofOtherIntangibleAssetsDetails">
        <link:definition>9954505 - Disclosure - Goodwill and Other Intangible Assets - Schedule of Carrying Amount of Other Intangible Assets (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillandOtherIntangibleAssetsScheduleofCarryingAmountofOtherIntangibleAssetsDetails_1" roleURI="http://www.aosmith.com/role/GoodwillandOtherIntangibleAssetsScheduleofCarryingAmountofOtherIntangibleAssetsDetails_1">
        <link:definition>9954505 - Disclosure - Goodwill and Other Intangible Assets - Schedule of Carrying Amount of Other Intangible Assets (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillandOtherIntangibleAssetsNarrativeDetails" roleURI="http://www.aosmith.com/role/GoodwillandOtherIntangibleAssetsNarrativeDetails">
        <link:definition>9954506 - Disclosure - Goodwill and Other Intangible Assets - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DebtScheduleofDebtDetails" roleURI="http://www.aosmith.com/role/DebtScheduleofDebtDetails">
        <link:definition>9954507 - Disclosure - Debt - Schedule of Debt (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DebtNarrativeDetails" roleURI="http://www.aosmith.com/role/DebtNarrativeDetails">
        <link:definition>9954508 - Disclosure - Debt - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DebtScheduleofMaturitiesofLongTermDebtDetails" roleURI="http://www.aosmith.com/role/DebtScheduleofMaturitiesofLongTermDebtDetails">
        <link:definition>9954509 - Disclosure - Debt - Schedule of Maturities of Long Term Debt (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockholdersEquityNarrativeDetails" roleURI="http://www.aosmith.com/role/StockholdersEquityNarrativeDetails">
        <link:definition>9954510 - Disclosure - Stockholders' Equity - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockholdersEquityChangesinAccumulatedOtherComprehensiveLossbyComponentDetails" roleURI="http://www.aosmith.com/role/StockholdersEquityChangesinAccumulatedOtherComprehensiveLossbyComponentDetails">
        <link:definition>9954511 - Disclosure - Stockholders' Equity - Changes in Accumulated Other Comprehensive Loss by Component (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockBasedCompensationNarrativeDetails" roleURI="http://www.aosmith.com/role/StockBasedCompensationNarrativeDetails">
        <link:definition>9954512 - Disclosure - Stock Based Compensation - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockBasedCompensationChangesinOptionAwardsAllofWhichRelatedtoCommonStockDetails" roleURI="http://www.aosmith.com/role/StockBasedCompensationChangesinOptionAwardsAllofWhichRelatedtoCommonStockDetails">
        <link:definition>9954513 - Disclosure - Stock Based Compensation - Changes in Option Awards All of Which Related to Common Stock (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockBasedCompensationNonvestedStockOptionsDetails" roleURI="http://www.aosmith.com/role/StockBasedCompensationNonvestedStockOptionsDetails">
        <link:definition>9954514 - Disclosure - Stock Based Compensation - Nonvested Stock Options (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockBasedCompensationScheduleofWeightedAverageFairValueperOptionatDateofGrantDetails" roleURI="http://www.aosmith.com/role/StockBasedCompensationScheduleofWeightedAverageFairValueperOptionatDateofGrantDetails">
        <link:definition>9954515 - Disclosure - Stock Based Compensation - Schedule of Weighted-Average Fair Value per Option at Date of Grant (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockBasedCompensationSummaryofShareUnitActivityUnderPlanDetails" roleURI="http://www.aosmith.com/role/StockBasedCompensationSummaryofShareUnitActivityUnderPlanDetails">
        <link:definition>9954516 - Disclosure - Stock Based Compensation - Summary of Share Unit Activity Under Plan (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockBasedCompensationScheduleofPerformanceStockUnitActivityDetails" roleURI="http://www.aosmith.com/role/StockBasedCompensationScheduleofPerformanceStockUnitActivityDetails">
        <link:definition>9954517 - Disclosure - Stock Based Compensation - Schedule of Performance Stock Unit Activity (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PensionandOtherPostretirementBenefitsNarrativeDetails" roleURI="http://www.aosmith.com/role/PensionandOtherPostretirementBenefitsNarrativeDetails">
        <link:definition>9954518 - Disclosure - Pension and Other Post-retirement Benefits - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PensionandOtherPostretirementBenefitsScheduleofChangesinBenefitObligationsPlanAssetsandFundedStatusofDefinedBenefitPensionandPostRetirementBenefitPlansDetails" roleURI="http://www.aosmith.com/role/PensionandOtherPostretirementBenefitsScheduleofChangesinBenefitObligationsPlanAssetsandFundedStatusofDefinedBenefitPensionandPostRetirementBenefitPlansDetails">
        <link:definition>9954519 - Disclosure - Pension and Other Post-retirement Benefits - Schedule of Changes in Benefit Obligations, Plan Assets and Funded Status of Defined Benefit Pension and Post-Retirement Benefit Plans (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PensionandOtherPostretirementBenefitsComponentsofCompanysNetPeriodicPensionCostsDetails" roleURI="http://www.aosmith.com/role/PensionandOtherPostretirementBenefitsComponentsofCompanysNetPeriodicPensionCostsDetails">
        <link:definition>9954520 - Disclosure - Pension and Other Post-retirement Benefits - Components of Company's Net Periodic Pension Costs (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PensionandOtherPostretirementBenefitsActuarialAssumptionsUsedtoDetermineBenefitObligationsDetails" roleURI="http://www.aosmith.com/role/PensionandOtherPostretirementBenefitsActuarialAssumptionsUsedtoDetermineBenefitObligationsDetails">
        <link:definition>9954521 - Disclosure - Pension and Other Post-retirement Benefits - Actuarial Assumptions Used to Determine Benefit Obligations (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PensionandOtherPostretirementBenefitsAssumptionsUsedtoDetermineNetPeriodicBenefitCostDetails" roleURI="http://www.aosmith.com/role/PensionandOtherPostretirementBenefitsAssumptionsUsedtoDetermineNetPeriodicBenefitCostDetails">
        <link:definition>9954522 - Disclosure - Pension and Other Post-retirement Benefits - Assumptions Used to Determine Net Periodic Benefit Cost (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PensionandOtherPostretirementBenefitsWeightedAssetAllocationsbyAssetCategoryDetails" roleURI="http://www.aosmith.com/role/PensionandOtherPostretirementBenefitsWeightedAssetAllocationsbyAssetCategoryDetails">
        <link:definition>9954523 - Disclosure - Pension and Other Post-retirement Benefits - Weighted Asset Allocations by Asset Category (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PensionandOtherPostretirementBenefitsFairValueMeasurementofPlanAssetsDetails" roleURI="http://www.aosmith.com/role/PensionandOtherPostretirementBenefitsFairValueMeasurementofPlanAssetsDetails">
        <link:definition>9954524 - Disclosure - Pension and Other Post-retirement Benefits - Fair Value Measurement of Plan Assets (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PensionandOtherPostretirementBenefitsReconciliationofFairValueMeasurementsUsingSignificantUnobservableInputsDetails" roleURI="http://www.aosmith.com/role/PensionandOtherPostretirementBenefitsReconciliationofFairValueMeasurementsUsingSignificantUnobservableInputsDetails">
        <link:definition>9954525 - Disclosure - Pension and Other Post-retirement Benefits - Reconciliation of Fair Value Measurements Using Significant Unobservable Inputs (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="PensionandOtherPostretirementBenefitsEstimatedFuturePaymentsDetails" roleURI="http://www.aosmith.com/role/PensionandOtherPostretirementBenefitsEstimatedFuturePaymentsDetails">
        <link:definition>9954526 - Disclosure - Pension and Other Post-retirement Benefits - Estimated Future Payments (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeInstrumentsNarrativeDetails" roleURI="http://www.aosmith.com/role/DerivativeInstrumentsNarrativeDetails">
        <link:definition>9954527 - Disclosure - Derivative Instruments - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeInstrumentsSummarybyContractualAmountsforDerivativesDesignatedasCashFlowHedgesDetails" roleURI="http://www.aosmith.com/role/DerivativeInstrumentsSummarybyContractualAmountsforDerivativesDesignatedasCashFlowHedgesDetails">
        <link:definition>9954528 - Disclosure - Derivative Instruments - Summary by Contractual Amounts for Derivatives Designated as Cash Flow Hedges (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeInstrumentsEffectofCashFlowHedgesontheConsolidatedStatementofEarningsDetails" roleURI="http://www.aosmith.com/role/DerivativeInstrumentsEffectofCashFlowHedgesontheConsolidatedStatementofEarningsDetails">
        <link:definition>9954529 - Disclosure - Derivative Instruments - Effect of Cash Flow Hedges on the Consolidated Statement of Earnings (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeInstrumentsSummaryofContractualAmountsforDerivativesnotDesignatedasHedgingInstrumentsDetailsDetails" roleURI="http://www.aosmith.com/role/DerivativeInstrumentsSummaryofContractualAmountsforDerivativesnotDesignatedasHedgingInstrumentsDetailsDetails">
        <link:definition>9954530 - Disclosure - Derivative Instruments - Summary of Contractual Amounts for Derivatives not Designated as Hedging Instruments (Details) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeInstrumentsEffectofForeignExchangeContractsontheConsolidatedStatementofEarningsDetails" roleURI="http://www.aosmith.com/role/DerivativeInstrumentsEffectofForeignExchangeContractsontheConsolidatedStatementofEarningsDetails">
        <link:definition>9954531 - Disclosure - Derivative Instruments - Effect of Foreign Exchange Contracts on the Consolidated Statement of Earnings (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesComponentsofProvisionforIncomeTaxesDetails" roleURI="http://www.aosmith.com/role/IncomeTaxesComponentsofProvisionforIncomeTaxesDetails">
        <link:definition>9954532 - Disclosure - Income Taxes - Components of Provision for Income Taxes (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesDifferenceBetweenProvisionforIncomeTaxesandUSFederalStatutoryRateDetails" roleURI="http://www.aosmith.com/role/IncomeTaxesDifferenceBetweenProvisionforIncomeTaxesandUSFederalStatutoryRateDetails">
        <link:definition>9954533 - Disclosure - Income Taxes - Difference Between Provision for Income Taxes and U.S. Federal Statutory Rate (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesComponentsofEarningBeforeIncomeTaxesDetails" roleURI="http://www.aosmith.com/role/IncomeTaxesComponentsofEarningBeforeIncomeTaxesDetails">
        <link:definition>9954534 - Disclosure - Income Taxes - Components of Earning Before Income Taxes (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesNarrativeDetails" roleURI="http://www.aosmith.com/role/IncomeTaxesNarrativeDetails">
        <link:definition>9954535 - Disclosure - Income Taxes - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesTaxEffectsofTemporaryDifferencesofAssetsandLiabilitiesDetails" roleURI="http://www.aosmith.com/role/IncomeTaxesTaxEffectsofTemporaryDifferencesofAssetsandLiabilitiesDetails">
        <link:definition>9954536 - Disclosure - Income Taxes - Tax Effects of Temporary Differences of Assets and Liabilities (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesReconciliationofNetOperatingLossesTaxCreditandValuationAllowancesDetails" roleURI="http://www.aosmith.com/role/IncomeTaxesReconciliationofNetOperatingLossesTaxCreditandValuationAllowancesDetails">
        <link:definition>9954537 - Disclosure - Income Taxes - Reconciliation of Net Operating Losses, Tax Credit and Valuation Allowances (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesReconciliationofUnrecognizedTaxBenefitsDetails" roleURI="http://www.aosmith.com/role/IncomeTaxesReconciliationofUnrecognizedTaxBenefitsDetails">
        <link:definition>9954538 - Disclosure - Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="CommitmentandContingenciesNarrativeDetails" roleURI="http://www.aosmith.com/role/CommitmentandContingenciesNarrativeDetails">
        <link:definition>9954539 - Disclosure - Commitment and Contingencies - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OperationsbySegmentNarrativeDetails" roleURI="http://www.aosmith.com/role/OperationsbySegmentNarrativeDetails">
        <link:definition>9954540 - Disclosure - Operations by Segment - Narrative (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OperationsbySegmentScheduleofSegmentEarningsDetails" roleURI="http://www.aosmith.com/role/OperationsbySegmentScheduleofSegmentEarningsDetails">
        <link:definition>9954541 - Disclosure - Operations by Segment - Schedule of Segment Earnings (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OperationsbySegmentAssetsDepreciationAndCapitalExpenditureBySegmentDetails" roleURI="http://www.aosmith.com/role/OperationsbySegmentAssetsDepreciationAndCapitalExpenditureBySegmentDetails">
        <link:definition>9954542 - Disclosure - Operations by Segment - Assets, Depreciation And Capital Expenditure By Segment (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="OperationsbySegmentNetSalesandLongLivedAssetsbyGeographicLocationDetails" roleURI="http://www.aosmith.com/role/OperationsbySegmentNetSalesandLongLivedAssetsbyGeographicLocationDetails">
        <link:definition>9954543 - Disclosure - Operations by Segment - Net Sales and Long-Lived Assets by Geographic Location (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ScheduleIIValuationandQualifyingAccountsDetails" roleURI="http://www.aosmith.com/role/ScheduleIIValuationandQualifyingAccountsDetails">
        <link:definition>9954544 - Disclosure - Schedule II - Valuation and Qualifying Accounts (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
    </xs:appinfo>
  </xs:annotation>
  <xs:element id="aos_PercentageMatchOfNextFivePercentOfContributionsMadeByParticipatingEmployees" abstract="false" name="PercentageMatchOfNextFivePercentOfContributionsMadeByParticipatingEmployees" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="aos_NumberOfFormerAndActiveEmployeesTheAnnuityPlanCovers" abstract="false" name="NumberOfFormerAndActiveEmployeesTheAnnuityPlanCovers" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="aos_EffectiveIncomeTaxRateReconciliationPensionPlanSettlementPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationPensionPlanSettlementPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="aos_AuditInformationAbstract" abstract="true" name="AuditInformationAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="aos_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueRollForward" abstract="true" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValueRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="aos_PostretirementMedicalBenefitsQualifyingAge" abstract="false" name="PostretirementMedicalBenefitsQualifyingAge" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="aos_BusinessCombinationConsiderationTransferredWorkingCapitalAdjustments" abstract="false" name="BusinessCombinationConsiderationTransferredWorkingCapitalAdjustments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_CommonStockVotingRightsMattersOtherThanElectionOfBoardOfDirectorsVotePerShare" abstract="false" name="CommonStockVotingRightsMattersOtherThanElectionOfBoardOfDirectorsVotePerShare" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:decimalItemType"/>
  <xs:element id="aos_AssetImpairmentChargesDomain" abstract="true" name="AssetImpairmentChargesDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aos_ReconciliationOfStatutoryFederalTaxRateTable" abstract="true" name="ReconciliationOfStatutoryFederalTaxRateTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="aos_LiabilityDefinedBenefitPlanPercentageOfTotal" abstract="false" name="LiabilityDefinedBenefitPlanPercentageOfTotal" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="aos_ShareRepurchaseProgramExciseTax" abstract="false" name="ShareRepurchaseProgramExciseTax" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_ProductLiabilityIndividualClaimMaximumAmount" abstract="false" name="ProductLiabilityIndividualClaimMaximumAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_ValuationAllowanceForTradeAndNotesReceivableMember" abstract="true" name="ValuationAllowanceForTradeAndNotesReceivableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_RestOfWorldMember" abstract="true" name="RestOfWorldMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustments" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustments" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="aos_ExerciseOfStockOptionsSharesSurrenderedAsProceeds" abstract="false" name="ExerciseOfStockOptionsSharesSurrenderedAsProceeds" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="aos_ScheduleOfSupplementalBalanceSheetInformationRelatedToLeasesTableTextBlock" abstract="false" name="ScheduleOfSupplementalBalanceSheetInformationRelatedToLeasesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="aos_PensionSettlementNonCashTaxes" abstract="false" name="PensionSettlementNonCashTaxes" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_DefinedBenefitPlanFairValueOfPlanAssetsIncludingNoninvestmentPlanAssets" abstract="false" name="DefinedBenefitPlanFairValueOfPlanAssetsIncludingNoninvestmentPlanAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_AllOtherMember" abstract="true" name="AllOtherMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_DefinedBenefitPlanPensionPlanTerminatedInPriorYearMember" abstract="true" name="DefinedBenefitPlanPensionPlanTerminatedInPriorYearMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aos_DefinedBenefitPlanFairValueOfNonInvestmentPlanAssets" abstract="false" name="DefinedBenefitPlanFairValueOfNonInvestmentPlanAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_PercentageMatchOfFirstOnePercentOfContributionsMadeByParticipatingEmployees" abstract="false" name="PercentageMatchOfFirstOnePercentOfContributionsMadeByParticipatingEmployees" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="aos_GoodwillAndOtherIntangiblesLineItems" abstract="true" name="GoodwillAndOtherIntangiblesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="aos_ScheduleOfReconciliationOfTaxLossCarryoversCreditCarryoversAndValuationAllowancesTableTableTextBlock" abstract="false" name="ScheduleOfReconciliationOfTaxLossCarryoversCreditCarryoversAndValuationAllowancesTableTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="aos_WaterTreatmentProductsMember" abstract="true" name="WaterTreatmentProductsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_ReconciliationOfNetOperatingLossesAndTaxCreditsRollForward" abstract="true" name="ReconciliationOfNetOperatingLossesAndTaxCreditsRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="aos_DeferredTaxAssetEnvironmental" abstract="false" name="DeferredTaxAssetEnvironmental" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsIncludingGoodwill" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsIncludingGoodwill" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_ShareBasedCompensationArrangementByShareBasedPaymentAwardPotentialPayoutPercentOfTargetAwards" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPotentialPayoutPercentOfTargetAwards" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="aos_OrganizationAndSummaryOfSignificantAccountingPoliciesTable" abstract="true" name="OrganizationAndSummaryOfSignificantAccountingPoliciesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="aos_NumberOfWholesaleDistributors" abstract="false" name="NumberOfWholesaleDistributors" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="aos_ImpairmentOrDisposalOfLongLivedIntangibleAssetsImpairmentPolicyTextBlock" abstract="false" name="ImpairmentOrDisposalOfLongLivedIntangibleAssetsImpairmentPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="aos_RentIncentivesAndDeferrals" abstract="false" name="RentIncentivesAndDeferrals" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_CommitmentsAndContingenciesLineItems" abstract="true" name="CommitmentsAndContingenciesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="aos_OtherForeignMember" abstract="true" name="OtherForeignMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_AssetImpairmentChargesAxis" abstract="true" name="AssetImpairmentChargesAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="aos_WaterHeatersAndRelatedPartsMember" abstract="true" name="WaterHeatersAndRelatedPartsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNonvestedWeightedAverageExercisePriceRollForward" abstract="true" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsNonvestedWeightedAverageExercisePriceRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="aos_PensionSettlementIncomeExpenseNonCashTaxes" abstract="false" name="PensionSettlementIncomeExpenseNonCashTaxes" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_LineOfCreditFacilityAccordionFeatureHigherBorrowingCapacityOption" abstract="false" name="LineOfCreditFacilityAccordionFeatureHigherBorrowingCapacityOption" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_BoilersAndRelatedPartsMember" abstract="true" name="BoilersAndRelatedPartsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_TermNotesWithInsuranceCompaniesMember" abstract="true" name="TermNotesWithInsuranceCompaniesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_MinimumPercentageOfAmountLikelyToBeRealizedUponUltimateSettlementToRecognizeTaxBenefits" abstract="false" name="MinimumPercentageOfAmountLikelyToBeRealizedUponUltimateSettlementToRecognizeTaxBenefits" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="aos_PercentageOfFederalIncomeTaxLiabilityOffsetByDividendReceivedDeduction" abstract="false" name="PercentageOfFederalIncomeTaxLiabilityOffsetByDividendReceivedDeduction" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="aos_CommonStockVotingRightsAllowablePercentageOfBoardOfDirectorsToElect" abstract="false" name="CommonStockVotingRightsAllowablePercentageOfBoardOfDirectorsToElect" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="aos_VestingOfShareUnits" abstract="false" name="VestingOfShareUnits" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_CommitmentsAndContingenciesTable" abstract="true" name="CommitmentsAndContingenciesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="aos_NetOperatingLossesAndTaxCredits" abstract="false" name="NetOperatingLossesAndTaxCredits" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_PensionSettlementNonCashTaxesReleaseOfStrandedTaxEffects" abstract="false" name="PensionSettlementNonCashTaxesReleaseOfStrandedTaxEffects" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_AmortizationOfAdvertisingCosts" abstract="false" name="AmortizationOfAdvertisingCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_CommodityFuturesContractsMember" abstract="true" name="CommodityFuturesContractsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_AssetsLesseeAbstract" abstract="true" name="AssetsLesseeAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="aos_LitigationSettlementTaxExpense" abstract="false" name="LitigationSettlementTaxExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_LesseeOperatingLeaseTerminationPeriod" abstract="false" name="LesseeOperatingLeaseTerminationPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="aos_AOSmithCombinedCompensationPlanMember" abstract="true" name="AOSmithCombinedCompensationPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_DistributorRebateAccruals" abstract="false" name="DistributorRebateAccruals" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_ProductWarrantyPeriod" abstract="false" name="ProductWarrantyPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="aos_AnnuallyMember" abstract="true" name="AnnuallyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_DefinedBenefitPensionPlanTerminationSettlementOfPlanLiabilitiesThroughLumpSumPayments" abstract="false" name="DefinedBenefitPensionPlanTerminationSettlementOfPlanLiabilitiesThroughLumpSumPayments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_CommonStockConversionBasisRatio" abstract="false" name="CommonStockConversionBasisRatio" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="aos_PensionSettlementNonCashTaxesTaxEffectOnPretaxExpense" abstract="false" name="PensionSettlementNonCashTaxesTaxEffectOnPretaxExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_UndistributedEarningsOfForeignSubsidiariesIncludingTemporarilyAndPermanentlyReinvested" abstract="false" name="UndistributedEarningsOfForeignSubsidiariesIncludingTemporarilyAndPermanentlyReinvested" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_StockIssuedDuringPeriodValueStockIncentiveAndDirectorsCompensation" abstract="false" name="StockIssuedDuringPeriodValueStockIncentiveAndDirectorsCompensation" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_ImpairmentRecordedAsNetReductionToAssetsAndLiabilitiesMember" abstract="true" name="ImpairmentRecordedAsNetReductionToAssetsAndLiabilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_NorthAmericaSegmentMember" abstract="true" name="NorthAmericaSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_BusinessCombinationAcquisitionRelatedCostsTaxExpenseBenefit" abstract="false" name="BusinessCombinationAcquisitionRelatedCostsTaxExpenseBenefit" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_ImpairmentRecordedForAnticipatedLiquidationOfCumulativeForeignCurrencyTranslationAdjustmentRecordedInAccruedLiabilitiesMember" abstract="true" name="ImpairmentRecordedForAnticipatedLiquidationOfCumulativeForeignCurrencyTranslationAdjustmentRecordedInAccruedLiabilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_UndistributedEarningsOfForeignSubsidiariesNotPermanentlyReinvested" abstract="false" name="UndistributedEarningsOfForeignSubsidiariesNotPermanentlyReinvested" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_CommonStockClassUndefinedMember" abstract="true" name="CommonStockClassUndefinedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_MaximumAggregateProductLiabilityInsuranceCoverage" abstract="false" name="MaximumAggregateProductLiabilityInsuranceCoverage" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_OrganizationAndSummaryOfSignificantAccountingPoliciesLineItems" abstract="true" name="OrganizationAndSummaryOfSignificantAccountingPoliciesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="aos_PrivatelyHeldWaterTreatmentCompanyMember" abstract="true" name="PrivatelyHeldWaterTreatmentCompanyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_CustomerTwoMember" abstract="true" name="CustomerTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsNetOfCashAcquired" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsNetOfCashAcquired" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_ReconciliationOfValuationAllowanceDeferredTaxAssetRollForward" abstract="true" name="ReconciliationOfValuationAllowanceDeferredTaxAssetRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="aos_AmortizationPeriodOfAdvertisingCosts" abstract="false" name="AmortizationPeriodOfAdvertisingCosts" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="aos_MarketableSecuritiesMaturityPeriod" abstract="false" name="MarketableSecuritiesMaturityPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="aos_DeferredTaxAssetTaxLossAndCreditCarryovers" abstract="false" name="DeferredTaxAssetTaxLossAndCreditCarryovers" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_DefinedBenefitPensionPlanMember" abstract="true" name="DefinedBenefitPensionPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodFairValue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_NetOperatingLossesAndTaxCreditsIncreaseDecreaseAmount" abstract="false" name="NetOperatingLossesAndTaxCreditsIncreaseDecreaseAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_RepurchaseOfInventoryMember" abstract="true" name="RepurchaseOfInventoryMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_CustomerOneMember" abstract="true" name="CustomerOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustmentsWeightedAverageGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceAdjustmentsWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
  <xs:element id="aos_DeferredTaxAssetsAccountsReceivable" abstract="false" name="DeferredTaxAssetsAccountsReceivable" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_OperatingLeaseTermAndDiscountRateAbstract" abstract="true" name="OperatingLeaseTermAndDiscountRateAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="aos_GiantFactoriesIncMember" abstract="true" name="GiantFactoriesIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_ReclassificationPeriodForEffectivePortionOfContract" abstract="false" name="ReclassificationPeriodForEffectivePortionOfContract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="aos_DefinedBenefitPlanAndDefinedContributionPlanPeriodicBenefitCost" abstract="false" name="DefinedBenefitPlanAndDefinedContributionPlanPeriodicBenefitCost" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_DefinedBenefitPlanNumberOfPlans" abstract="false" name="DefinedBenefitPlanNumberOfPlans" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="aos_AllOtherRestOfWorldMember" abstract="true" name="AllOtherRestOfWorldMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_TerminatedAcquisitionMember" abstract="true" name="TerminatedAcquisitionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_ReconciliationOfStatutoryFederalTaxRateLineItems" abstract="true" name="ReconciliationOfStatutoryFederalTaxRateLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="aos_RevenueFromContractWithCustomerPaymentTerms" abstract="false" name="RevenueFromContractWithCustomerPaymentTerms" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="aos_LongTermDebtFixedInterestPayment" abstract="false" name="LongTermDebtFixedInterestPayment" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_ScheduleOfGoodwillAndOtherIntangiblesTable" abstract="true" name="ScheduleOfGoodwillAndOtherIntangiblesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="aos_WaterHeatersMember" abstract="true" name="WaterHeatersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="aos_PaymentsForProceedsFromStockOptionsActivity" abstract="false" name="PaymentsForProceedsFromStockOptionsActivity" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_AdjustmentsToAdditionalPaidInCapitalShareUnitsIssued" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalShareUnitsIssued" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="aos_DefinedBenefitPensionPlanTerminationSettlementOfPlanLiabilitiesThroughPurchaseOfAnnuities" abstract="false" name="DefinedBenefitPensionPlanTerminationSettlementOfPlanLiabilitiesThroughPurchaseOfAnnuities" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
