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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>0001214412-09-000022.txt : 20090501
<SEC-HEADER>0001214412-09-000022.hdr.sgml : 20090501
<ACCEPTANCE-DATETIME>20090501170245
ACCESSION NUMBER:		0001214412-09-000022
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090422
FILED AS OF DATE:		20090501
DATE AS OF CHANGE:		20090501

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LARSON JEFFREY E
		CENTRAL INDEX KEY:			0001238743

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34224
		FILM NUMBER:		09790273

	MAIL ADDRESS:	
		STREET 1:		6300 BRIDGE POINT PARKWAY
		STREET 2:		BLDG 2 SUITE 500
		CITY:			AUSTIN
		STATE:			TX
		ZIP:			78730

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BRIGHAM EXPLORATION CO
		CENTRAL INDEX KEY:			0001034755
		STANDARD INDUSTRIAL CLASSIFICATION:	CRUDE PETROLEUM & NATURAL GAS [1311]
		IRS NUMBER:				752692967
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		6300 BRIDGE POINT PARKWAY
		STREET 2:		BLDG 2 SUITE 500
		CITY:			AUSTIN
		STATE:			TX
		ZIP:			78730
		BUSINESS PHONE:		5124273300

	MAIL ADDRESS:	
		STREET 1:		6300 BRIDGE POINT PARKWAY
		STREET 2:		BLDG 2 SUITE 500
		CITY:			AUSTIN
		STATE:			TX
		ZIP:			78730
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2009-04-22</periodOfReport>

    <dateOfOriginalSubmission>2009-04-24</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001034755</issuerCik>
        <issuerName>BRIGHAM EXPLORATION CO</issuerName>
        <issuerTradingSymbol>BEXP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001238743</rptOwnerCik>
            <rptOwnerName>LARSON JEFFREY E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>6300 BRIDGE POINT PARKWAY</rptOwnerStreet1>
            <rptOwnerStreet2>BLDG 2 SUITE 500</rptOwnerStreet2>
            <rptOwnerCity>AUSTIN</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>78730</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Executive V.P. Exploration</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value $.01</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2009-04-22</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>4038</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>54207</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Restricted stock grant made pursuant to the 1997 Incentive Plan of Brigham Exploration Company.  The granted restricted stock vests on September 22, 2009.  In a Form 4 filed on April 24, 2009, the reporting person reported acquiring 8,500 shares of restricted stock pursuant to the Company's 1997 Incentive Plan.  The Company subsequently determined that the grant exceeded the amount of shares authorized under the Company's 1997 Incentive Plan and a portion of the grant was void.  The reporting person is filing this amendment to report the correct amount of shares acquired.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Jeffery E. Larson</signatureName>
        <signatureDate>2009-05-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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