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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0000230557-04-000148.txt : 20040810
<SEC-HEADER>0000230557-04-000148.hdr.sgml : 20040810
<ACCEPTANCE-DATETIME>20040810150943
ACCESSION NUMBER:		0000230557-04-000148
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20040809
FILED AS OF DATE:		20040810

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			CONNELL RICHARD F
		CENTRAL INDEX KEY:			0001208245

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-08641
		FILM NUMBER:		04964339

	MAIL ADDRESS:	
		STREET 1:		40 WANTAGE AVE
		CITY:			BRANCHVILLE
		STATE:			NJ
		ZIP:			07890

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SELECTIVE INSURANCE GROUP INC
		CENTRAL INDEX KEY:			0000230557
		STANDARD INDUSTRIAL CLASSIFICATION:	FIRE, MARINE & CASUALTY INSURANCE [6331]
		IRS NUMBER:				222168890
		STATE OF INCORPORATION:			NJ
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		40 WANTAGE AVENUE
		CITY:			BRANCHVILLE
		STATE:			NJ
		ZIP:			07890
		BUSINESS PHONE:		2019483000

	MAIL ADDRESS:	
		STREET 1:		40 WANTAGE AVE
		STREET 2:		40 WANTAGE AVE
		CITY:			BRANCHVILLE
		STATE:			NJ
		ZIP:			07890

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SRI CORP
		DATE OF NAME CHANGE:	19860508
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>c0001208245d20040810f4f.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-08-09</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000230557</issuerCik>
        <issuerName>SELECTIVE INSURANCE GROUP INC</issuerName>
        <issuerTradingSymbol>SIGI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001208245</rptOwnerCik>
            <rptOwnerName>CONNELL RICHARD F</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>40 WANTAGE AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BRANCHVILLE</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07890</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Executive Vice President &amp; Chi</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-08-09</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1389</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>27916.68</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Includes 305.680 shares acquired on August 8, 2004, through the Dividend Reinvestment feature of Restricted Stock which was granted under Selective's Employee Stock Option Plan II and vested on August 8, 2004.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Richard F Connell</signatureName>
        <signatureDate>2004-08-10</signatureDate>
    </ownerSignature>
</ownershipDocument>

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