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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 TqJy+3p2SLbxQ9efhwmsbr/MHtbmwow+BeYHhtxzssKH/eslRMwxTzPaGm5DPf9Y
 yuU+YW0X2yolYQL5BSIAAg==

<SEC-DOCUMENT>0001140361-10-042143.txt : 20101025
<SEC-HEADER>0001140361-10-042143.hdr.sgml : 20101025
<ACCEPTANCE-DATETIME>20101025152728
ACCESSION NUMBER:		0001140361-10-042143
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20101022
FILED AS OF DATE:		20101025
DATE AS OF CHANGE:		20101025

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			THOMPSON GEOFFREY A
		CENTRAL INDEX KEY:			0001272736

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-09235
		FILM NUMBER:		101139807

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			THOR INDUSTRIES INC
		CENTRAL INDEX KEY:			0000730263
		STANDARD INDUSTRIAL CLASSIFICATION:	MOTOR HOMES [3716]
		IRS NUMBER:				930768752
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0731

	BUSINESS ADDRESS:	
		STREET 1:		419 W PIKE ST
		CITY:			JACKSON CENTER
		STATE:			OH
		ZIP:			45334
		BUSINESS PHONE:		9375966849

	MAIL ADDRESS:	
		STREET 1:		419 W PIKE STREET
		CITY:			JACKSON CENTER
		STATE:			OH
		ZIP:			45334
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-10-22</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000730263</issuerCik>
        <issuerName>THOR INDUSTRIES INC</issuerName>
        <issuerTradingSymbol>THO</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001272736</rptOwnerCik>
            <rptOwnerName>THOMPSON GEOFFREY A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O THOR INDUSTRIES INC</rptOwnerStreet1>
            <rptOwnerStreet2>419 W PIKE ST</rptOwnerStreet2>
            <rptOwnerCity>JACKSON CENTER</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>45334-0629</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-10-22</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>600</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>31.584</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Geoffrey A. Thompson</signatureName>
        <signatureDate>2010-10-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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