<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-03-15</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001013934</issuerCik>
        <issuerName>STRAYER EDUCATION INC</issuerName>
        <issuerTradingSymbol>STRA</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001018327</rptOwnerCik>
            <rptOwnerName>KLINSKY STEVEN B</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O STRAYER EDUCATION</rptOwnerStreet1>
            <rptOwnerStreet2>712 5TH AVE 23RD FL</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10019</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-03-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>C</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1855139</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>26</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1855139</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-03-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1855139</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>101.04</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Series A Convertible Preferred Stock</value>
                <footnoteId id="F4"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>26</value>
                <footnoteId id="F5"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2004-03-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>C</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1855139</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>26</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F6"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F7"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1855139</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>780708</value>
                    <footnoteId id="F8"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">On March 9, 2004, the Issuer, New Mountain Strayer Trust (the &quot;Trust&quot;), New Mountain Partners, L.P. (&quot;New Mountain&quot;), MidOcean Capital Investors, L.P. (as successor to DB Capital Investors, L.P.)(&quot;MidOcean&quot;), Robert S. Silberman, an individual selling stockholder (&quot;Silberman&quot;), Scott W. Steffey, an individual selling stockholder (&quot;Steffey&quot;), Mark C. Brown, an individual selling stockholder (&quot;Brown&quot;), Steven A. McArthur, an individual selling stockholder (&quot;McArthur&quot;) and Kevin P. O'Reagan, an individual selling stockholder (&quot;O'Reagan&quot;) (the Trust, MidOcean, New Mountain, Silberman, Steffey, Brown, McArthur and O'Reagan are referred to collectively as the &quot;2004 Selling Stockholders&quot;) and Credit Suisse First Boston LLC (&quot;CSFB LLC&quot;), Banc of America Securities LLC (&quot;Banc of America&quot;), Legg Mason Wood Walker, Incorporated (&quot;Legg Mason&quot;), Lehman Brothers Inc.</footnote>
        <footnote id="F2">(&quot;Lehman&quot;), Thomas Weisel Partners LLC (&quot;Thomas Weisel&quot;) and J.P. Morgan Securities Inc. (&quot;J.P. Morgan&quot;) (CSFB LLC, Banc of America, Legg Mason, Lehman, Thomas Weisel and J.P. Morgan are referred to collectively as the &quot;2004 Underwriters&quot;), as representatives of the several underwriters, entered into an underwriting agreement (the &quot;2004 Underwriting Agreement&quot;) in connection with the 2004 Selling Stockholders' planned disposition of up to 3,450,000 shares of Common Stock pursuant to a Registration Statement on Form S-3 (File No. 333-112449)  (including up to 450,000 shares of Common Stock subject to the 2004 Underwriters' over-allotment option (the &quot;2004 Over-allotment Option&quot;)).  On March 15, 2004, pursuant to the 2004 Underwriting Agreement, the 2004 Underwriters acquired 1,855,139 shares of Common Stock owned by New Mountain at a price of $105.25 per share, less underwriting discounts and commissions of $4.21 per share, in connection with the public resale of the Common Stock.</footnote>
        <footnote id="F3">The Reporting Person is the sole member of New Mountain GP, LLC, which is the General Partner of New Mountain Investments, L.P., which is the General Partner of New Mountain.</footnote>
        <footnote id="F4">The Series A Convertible Preferred Stock is subject to certain restrictions as set forth in the Articles Supplementary of the Issuer, the Shareholders' Agreement, dated as of March 16, 2001, by and between New Mountain and MidOcean, the Letter Agreement, dated November 14, 2002, among the Issuer, New Mountain and MidOcean, the February 2004 Letter Agreement, dated February 3, 2004, among the Issuer, New Mountain and MidOcean, and the March 2004 Letter Agreement, dated March 9, 2004, among the Issuer, New Mountain, MidOcean and the Trust.</footnote>
        <footnote id="F5">The conversion price of the Series A Convertible Preferred Stock is subject to antidilution and other adjustments.</footnote>
        <footnote id="F6">The Series A Convertible Preferred Stock is immediately exercisable.</footnote>
        <footnote id="F7">There is no expiration date for the Series A Convertible Preferred Stock.</footnote>
        <footnote id="F8">The number of shares of Common Stock underlying the Series A Convertible Preferred Stock shall increase as dividends accumulate and compound on a daily basis.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Steven B. Klinsky</signatureName>
        <signatureDate>2004-03-15</signatureDate>
    </ownerSignature>
</ownershipDocument>

