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<SEC-DOCUMENT>0000091142-07-000037.txt : 20070522
<SEC-HEADER>0000091142-07-000037.hdr.sgml : 20070522
<ACCEPTANCE-DATETIME>20070522104704
ACCESSION NUMBER:		0000091142-07-000037
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20070521
FILED AS OF DATE:		20070522
DATE AS OF CHANGE:		20070522

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MASSA RONALD E
		CENTRAL INDEX KEY:			0001236638

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-00475
		FILM NUMBER:		07870103

	BUSINESS ADDRESS:	
		STREET 1:		A O SMITH CORP
		STREET 2:		11270 WEST PARK PLACE
		CITY:			MILWAUKEE
		STATE:			WI
		ZIP:			53224
		BUSINESS PHONE:		4143594000

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SMITH A O CORP
		CENTRAL INDEX KEY:			0000091142
		STANDARD INDUSTRIAL CLASSIFICATION:	MOTORS & GENERATORS [3621]
		IRS NUMBER:				390619790
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		P O BOX 245009
		CITY:			MILWAUKEE
		STATE:			WI
		ZIP:			53224-9509
		BUSINESS PHONE:		4143594000

	MAIL ADDRESS:	
		STREET 1:		P O BOX 245009
		CITY:			MILWAUKEE
		STATE:			WI
		ZIP:			53224-9509
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
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    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2007-05-21</periodOfReport>

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            <rptOwnerStreet2>12100 WEST PARK PLACE</rptOwnerStreet2>
            <rptOwnerCity>MILWAUKEE</rptOwnerCity>
            <rptOwnerState>WI</rptOwnerState>
            <rptOwnerZipCode>53224</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Executive Vice President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

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                <transactionCode>S</transactionCode>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
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                <value>Common Stock</value>
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                <transactionFormType>4</transactionFormType>
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            <transactionAmounts>
                <transactionShares>
                    <value>1100</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>39.16</value>
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                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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                <sharesOwnedFollowingTransaction>
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                <transactionShares>
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                    <value>0</value>
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                    <value>D</value>
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            <exerciseDate>
                <value>1999-10-05</value>
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            <expirationDate>
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                <underlyingSecurityTitle>
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                    <value>D</value>
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            <exerciseDate>
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    </derivativeTable>

    <footnotes>
        <footnote id="F1">Options were granted on 10/06/1998 under the A. O. Smith Corporation 1990 Long-Term Executive Incentive Compensation Plan, a Rule 16b-3 Plan.</footnote>
        <footnote id="F2">Options were granted on 10/11/2002 under the A. O. Smith Combined Executive Incentive Compensation Plan, a Rule 16b-3 Plan.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Kenneth J. Maciolek, Attorney-in-Fact for Ronald E. Massa</signatureName>
        <signatureDate>2007-05-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----
