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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0000091142-09-000037.txt : 20090723
<SEC-HEADER>0000091142-09-000037.hdr.sgml : 20090723
<ACCEPTANCE-DATETIME>20090723105416
ACCESSION NUMBER:		0000091142-09-000037
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090721
FILED AS OF DATE:		20090723
DATE AS OF CHANGE:		20090723

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			O TOOLE ROBERT J
		CENTRAL INDEX KEY:			0001187525

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-00475
		FILM NUMBER:		09958485

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>
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            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>RIVER HILLS</rptOwnerCity>
            <rptOwnerState>WI</rptOwnerState>
            <rptOwnerZipCode>53217</rptOwnerZipCode>
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    <footnotes>
        <footnote id="F1">Granted on 10/11/2002 under the A. O. Smith Corporation Long-Term Executive Incentive Compensation Plan, a Rule 16B-3 Plan.</footnote>
        <footnote id="F2">Granted on 10/07/2003 under the A. O. Smith Combined Executive Incentive Compensation Plan, a Rule 16B-3 Plan.</footnote>
        <footnote id="F3">Granted on 10/12/2004 under the A. O. Smith Combined Executive Incentive Compensation Plan, a Rule 16B-3 Plan.</footnote>
        <footnote id="F4">Granted on 10/11/2005 under the A. O. Smith Combined Executive Incentive Compensation Plan, a Rule 16B-3 Plan. The options became exercisable in three equal annual installments of 1/3 of the award starting on 10/10/2006.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Kenneth J. Maciolek, Attorney-in-Fact for Robert J. O'Toole</signatureName>
        <signatureDate>2009-07-23</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
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</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----
