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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,
 LY4GSQ7VHKpJYa+ZsdIzVyfLCyACe00nw3nQ1V0PSxM1XK1tGX6OcOdKMSRPnxHv
 lKNbEXcjw423ThlOW6qXkQ==

<SEC-DOCUMENT>0001179110-04-017337.txt : 20040831
<SEC-HEADER>0001179110-04-017337.hdr.sgml : 20040831
<ACCEPTANCE-DATETIME>20040831150438
ACCESSION NUMBER:		0001179110-04-017337
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20040830
FILED AS OF DATE:		20040831
DATE AS OF CHANGE:		20040831

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			GANDER MOUNTAIN CO
		CENTRAL INDEX KEY:			0001277475
		STANDARD INDUSTRIAL CLASSIFICATION:	RETAIL-MISCELLANEOUS SHOPPING GOODS STORES [5940]
		IRS NUMBER:				411990949
		STATE OF INCORPORATION:			MN

	BUSINESS ADDRESS:	
		STREET 1:		4567 AMERICAN BLVD.
		CITY:			MINNEAPOLIS
		STATE:			MN
		ZIP:			55437

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BOHN KAREN
		CENTRAL INDEX KEY:			0001274622

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-50659
		FILM NUMBER:		041008092

	MAIL ADDRESS:	
		STREET 1:		215 S CASCADE ST
		CITY:			FERGUS FALLS
		STATE:			MN
		ZIP:			565372801
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-08-30</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001277475</issuerCik>
        <issuerName>GANDER MOUNTAIN CO</issuerName>
        <issuerTradingSymbol>GMTN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001274622</rptOwnerCik>
            <rptOwnerName>BOHN KAREN</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>6620 IROQUOIS TRAIL</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>EDINA</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55439</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>2004-08-30</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>400</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>19.929</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>400</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By children</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>/s/ Jonathan R. Zimmerman on behalf of Karen M. Bohn</signatureName>
        <signatureDate>2004-08-31</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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