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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>0001193096-06-000006.txt : 20060707
<SEC-HEADER>0001193096-06-000006.hdr.sgml : 20060707
<ACCEPTANCE-DATETIME>20060707184752
ACCESSION NUMBER:		0001193096-06-000006
CONFORMED SUBMISSION TYPE:	5
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060630
FILED AS OF DATE:		20060707
DATE AS OF CHANGE:		20060707

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MICROSOFT CORP
		CENTRAL INDEX KEY:			0000789019
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		IRS NUMBER:				911144442
		STATE OF INCORPORATION:			WA
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		ONE MICROSOFT WAY #BLDG 8
		STREET 2:		NORTH OFFICE 2211
		CITY:			REDMOND
		STATE:			WA
		ZIP:			98052
		BUSINESS PHONE:		4258828080

	MAIL ADDRESS:	
		STREET 1:		ONE MICROSOFT WAY - BLDG 8
		STREET 2:		NORTH OFFICE 2211
		CITY:			REDMOND
		STATE:			WA
		ZIP:			98052-6399

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BURGUM DOUGLAS J
		CENTRAL INDEX KEY:			0001054822

	FILING VALUES:
		FORM TYPE:		5
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-14278
		FILM NUMBER:		06952259

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		7012810550

	MAIL ADDRESS:	
		STREET 1:		1701 SW 38TH ST
		CITY:			FARGO
		STATE:			ND
		ZIP:			58103
</SEC-HEADER>
<DOCUMENT>
<TYPE>5
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>5</documentType>

    <periodOfReport>2006-06-30</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <form3HoldingsReported>0</form3HoldingsReported>

    <form4TransactionsReported>0</form4TransactionsReported>

    <issuer>
        <issuerCik>0000789019</issuerCik>
        <issuerName>MICROSOFT CORP</issuerName>
        <issuerTradingSymbol>MSFT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001054822</rptOwnerCik>
            <rptOwnerName>BURGUM DOUGLAS J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>ONE MICROSOFT WAY</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>REDMOND</rptOwnerCity>
            <rptOwnerState>WA</rptOwnerState>
            <rptOwnerZipCode>98052-6399</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior Vice President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>600114</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6238</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By 401(k)</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Includes 643 shares acquired on March 31, 2006 and 280 shares acquired on June 30, 2006 under the Microsoft employee stock purchase plan.</footnote>
        <footnote id="F2">401(k) balance as of June 30, 2006.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Keith R. Dolliver, Attorney-in-Fact for Douglas J. Burgum</signatureName>
        <signatureDate>2006-07-07</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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