-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 QloCaoanc/PP1I+ynW18guLihtmmg3n3TdicrnGbChqn8sR44TQGu0IE8hF9tudt
 qVZc3Wtor4v4ncWDNCJ45g==

<SEC-DOCUMENT>0000793547-10-000005.txt : 20100308
<SEC-HEADER>0000793547-10-000005.hdr.sgml : 20100308
<ACCEPTANCE-DATETIME>20100308163003
ACCESSION NUMBER:		0000793547-10-000005
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100305
FILED AS OF DATE:		20100308
DATE AS OF CHANGE:		20100308

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Blakeney H J Mervyn
		CENTRAL INDEX KEY:			0001303292

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-15886
		FILM NUMBER:		10664074

	MAIL ADDRESS:	
		STREET 1:		20 RAWLINGS STREET
		CITY:			LONDON
		STATE:			X0
		ZIP:			SW3 2LS

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NAVIGATORS GROUP INC
		CENTRAL INDEX KEY:			0000793547
		STANDARD INDUSTRIAL CLASSIFICATION:	FIRE, MARINE & CASUALTY INSURANCE [6331]
		IRS NUMBER:				133138397
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		6 INTERNATIONAL DR
		STREET 2:		SUITE 100
		CITY:			RYE BROOK
		STATE:			NY
		ZIP:			10573
		BUSINESS PHONE:		9149348999

	MAIL ADDRESS:	
		STREET 1:		6 INTERNATIONAL DR
		STREET 2:		SUITE 100
		CITY:			RYE BROOK
		STATE:			NY
		ZIP:			10573
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-03-05</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000793547</issuerCik>
        <issuerName>NAVIGATORS GROUP INC</issuerName>
        <issuerTradingSymbol>NAVG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001303292</rptOwnerCik>
            <rptOwnerName>Blakeney H J Mervyn</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>20 RAWLINGS STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LONDON</rptOwnerCity>
            <rptOwnerState>X0</rptOwnerState>
            <rptOwnerZipCode>SW3 2LS</rptOwnerZipCode>
            <rptOwnerStateDescription>UNITED KINGDOM</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-03-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>637</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>47.11</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2713</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Restricted stock granted to director.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>H. J. Mervyn Blakeney</signatureName>
        <signatureDate>2010-03-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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