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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001203479-05-000004.txt : 20051104
<SEC-HEADER>0001203479-05-000004.hdr.sgml : 20051104
<ACCEPTANCE-DATETIME>20051104121416
ACCESSION NUMBER:		0001203479-05-000004
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20051102
FILED AS OF DATE:		20051104
DATE AS OF CHANGE:		20051104

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MICROSTRATEGY INC
		CENTRAL INDEX KEY:			0001050446
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		IRS NUMBER:				510323571
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1861 INTERNATIONAL DR
		CITY:			MCLEAN
		STATE:			VA
		ZIP:			22102
		BUSINESS PHONE:		7038488600

	MAIL ADDRESS:	
		STREET 1:		1861 INTERNATIONAL DR
		CITY:			MCLEAN
		STATE:			VA
		ZIP:			22102

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			RICKERTSEN CARL J
		CENTRAL INDEX KEY:			0001203479

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-24435
		FILM NUMBER:		051179183

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		7038488600

	MAIL ADDRESS:	
		STREET 1:		C/O MICROSTRATEGY INC
		STREET 2:		1861 INTERNATIONAL DR
		CITY:			MCLEAN
		STATE:			VA
		ZIP:			22102
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
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    <periodOfReport>2005-11-02</periodOfReport>

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        <issuerName>MICROSTRATEGY INC</issuerName>
        <issuerTradingSymbol>MSTR</issuerTradingSymbol>
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            <rptOwnerState>VA</rptOwnerState>
            <rptOwnerZipCode>22102</rptOwnerZipCode>
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        <nonDerivativeTransaction>
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            <transactionAmounts>
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                <transactionPricePerShare>
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                <transactionAcquiredDisposedCode>
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                <transactionAcquiredDisposedCode>
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                <directOrIndirectOwnership>
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                </directOrIndirectOwnership>
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                </natureOfOwnership>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
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                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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                <transactionShares>
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                <transactionPricePerShare>
                    <value>71.38</value>
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                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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                <sharesOwnedFollowingTransaction>
                    <value>1207</value>
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                <directOrIndirectOwnership>
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                </directOrIndirectOwnership>
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                    <value></value>
                </natureOfOwnership>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
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            <transactionDate>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionAmounts>
                <transactionShares>
                    <value>1207</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>71.39</value>
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                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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            <postTransactionAmounts>
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                    <value>0</value>
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                <directOrIndirectOwnership>
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                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Director Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>7.62</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-11-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2012-10-07</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Class A Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Director Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>20.69</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-11-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>5000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <value>2013-02-08</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Class A Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>5000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Separate open market sale transactions that were executed on 11/02/2005 at the same price have been reported on an aggregate basis on a single line in Table I.  The order in which sale transactions are set forth in Table I is not necessarily reflective of the sequence in which the sale transactions occurred in fact.</footnote>
        <footnote id="F2">The 2,000 shares exercised on 11/02/2005 pursuant to this stock option vested on 10/07/2005.  The remaining 4,000 shares subject to the stock option vest in two equal annual installments beginning on 10/07/2006.</footnote>
        <footnote id="F3">The 5,000 shares exercised on 11/02/2005 pursuant to this stock option vested on 02/08/2005.  The remaining 15,000 shares subject to the stock option vest in three equal annual installments beginning on 02/08/2006.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Carl John Rickertsen</signatureName>
        <signatureDate>2005-11-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----