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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001140361-11-004446.txt : 20110127
<SEC-HEADER>0001140361-11-004446.hdr.sgml : 20110127
<ACCEPTANCE-DATETIME>20110127162820
ACCESSION NUMBER:		0001140361-11-004446
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20110125
FILED AS OF DATE:		20110127
DATE AS OF CHANGE:		20110127

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Fenech Ronald
		CENTRAL INDEX KEY:			0001481268

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-09235
		FILM NUMBER:		11552548

	MAIL ADDRESS:	
		STREET 1:		419 WEST PIKE STREET
		CITY:			JACKSON CENTER
		STATE:			OH
		ZIP:			45334

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>2011-01-25</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001481268</rptOwnerCik>
            <rptOwnerName>Fenech Ronald</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O THOR INDUSTRIES, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>419 WEST PIKE STREET</rptOwnerStreet2>
            <rptOwnerCity>JACKSON CENTER</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>45334-0629</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior Group President</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2011-01-25</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>20000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>36.16</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>81239</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2011-01-25</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>36.22</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>71239</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The price reported in Column 4 is a weighted average price.  These shares were sold in multiple transactions at prices ranging from $35.77 to $36.34, inclusive.  The reporting person undertakes to provide to Thor Industries, Inc., any security holder of Thor Industries, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each price within the ranges set forth in footnotes (1) and (2) to this Form 4.</footnote>
        <footnote id="F2">The price reported in Column 4 is a weighted average price.  These shares were sold in multiple transactions at prices ranging from $36.20 to $36.27, inclusive.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Ronald Fenech</signatureName>
        <signatureDate>2011-01-26</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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