<SEC-DOCUMENT>0001127602-18-001069.txt : 20180104
<SEC-HEADER>0001127602-18-001069.hdr.sgml : 20180104
<ACCEPTANCE-DATETIME>20180104155306
ACCESSION NUMBER:		0001127602-18-001069
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180102
FILED AS OF DATE:		20180104
DATE AS OF CHANGE:		20180104

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BARTH CARIN MARCY
		CENTRAL INDEX KEY:			0001224909

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13461
		FILM NUMBER:		18509985

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			GROUP 1 AUTOMOTIVE INC
		CENTRAL INDEX KEY:			0001031203
		STANDARD INDUSTRIAL CLASSIFICATION:	RETAIL-AUTO DEALERS & GASOLINE STATIONS [5500]
		IRS NUMBER:				760506313
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		800 GESSNER
		STREET 2:		SUITE 500
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77024
		BUSINESS PHONE:		713-647-5700

	MAIL ADDRESS:	
		STREET 1:		800 GESSNER
		STREET 2:		SUITE 500
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77024
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-01-02</periodOfReport>

    <issuer>
        <issuerCik>0001031203</issuerCik>
        <issuerName>GROUP 1 AUTOMOTIVE INC</issuerName>
        <issuerTradingSymbol>GPI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001224909</rptOwnerCik>
            <rptOwnerName>BARTH CARIN MARCY</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>800 GESSNER</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 500</rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77077</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2131</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0</value>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2018-01-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2640</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2640</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2640</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each restricted stock unit represents a contingent right to receive one share of Group 1 Automotive, Inc. common stock.</footnote>
        <footnote id="F2">The vested restricted stock units held by a director are settled in shares of our common stock, cash, or a combination thereof, as determined by the Compensation Committee, upon the termination of the director's membership on our Board of Directors.  In the event that a director's membership on our Board of Directors is terminated for any reason other than retirement, death or disability, the director, for no consideration, forfeits to us all of the unvested shares of restricted stock or restricted stock units.  Any unvested restricted stock and any restricted stock units may not be sold or otherwise transferred.</footnote>
        <footnote id="F3">Vested shares will be delivered to the reporting person following retirement from the Board of Directors of Group 1 Automotive, Inc.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Beth Sibley, attorney-in-fact for Carin M. Barth</signatureName>
        <signatureDate>2018-01-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
