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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>0001104659-06-049103.txt : 20060726
<SEC-HEADER>0001104659-06-049103.hdr.sgml : 20060726
<ACCEPTANCE-DATETIME>20060726195736
ACCESSION NUMBER:		0001104659-06-049103
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060724
FILED AS OF DATE:		20060726
DATE AS OF CHANGE:		20060726

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MSC INDUSTRIAL DIRECT CO INC
		CENTRAL INDEX KEY:			0001003078
		STANDARD INDUSTRIAL CLASSIFICATION:	WHOLESALE-INDUSTRIAL MACHINERY & EQUIPMENT [5084]
		IRS NUMBER:				113289165
		STATE OF INCORPORATION:			NY
		FISCAL YEAR END:			0827

	BUSINESS ADDRESS:	
		STREET 1:		75 MAXESS RD
		CITY:			MELVILLE
		STATE:			NY
		ZIP:			11747
		BUSINESS PHONE:		516-812-2000

	MAIL ADDRESS:	
		STREET 1:		151 SUNNYSIDE BLVD
		CITY:			PLAINVIEW
		STATE:			NY
		ZIP:			11803

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			COX THOMAS
		CENTRAL INDEX KEY:			0001244856

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14130
		FILM NUMBER:		06982676

	BUSINESS ADDRESS:	
		STREET 1:		MSC INDUSTRIAL DIRECT CO INC
		STREET 2:		75 MAXESS RD
		CITY:			MELVILLE
		STATE:			NY
		ZIP:			11747
		BUSINESS PHONE:		5168122000
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>a4.xml
<DESCRIPTION>4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-07-24</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001003078</issuerCik>
        <issuerName>MSC INDUSTRIAL DIRECT CO INC</issuerName>
        <issuerTradingSymbol>MSM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001244856</rptOwnerCik>
            <rptOwnerName>COX THOMAS</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1></rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity></rptOwnerCity>
            <rptOwnerState></rptOwnerState>
            <rptOwnerZipCode></rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP of Sales</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock, $.001 par value</value>
            </securityTitle>
            <transactionDate>
                <value>2006-07-24</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>274</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>38.61</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>11419</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock, $.001 par value</value>
            </securityTitle>
            <transactionDate>
                <value>2006-07-25</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>13.9375</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>14419</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Options (right to buy)</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>13.9375</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2006-07-25</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2010-11-09</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>See Footnote</value>
                    <footnoteId id="F3"/>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>3000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5788</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Options to Purchase Issuer's Class A common stock, $.001 par value</footnote>
        <footnote id="F2">An option to purchase 50,000 shares of the Issuer's common stock, par value $.001 per share, was issued to the Reporting person under the Issuer's 1998 Stock Option Plan.  One fifth of such option became exercisable on each of November 9, 2001, November 9, 2002, November 9, 2003, November 9, 2004 and November 9, 2005.</footnote>
        <footnote id="F3">Class A Common Stock, $.001 par value.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Thomas Cox</signatureName>
        <signatureDate>2006-07-26</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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