<?xml version="1.0"?>

<ownershipDocument>

    <documentType>4</documentType>

    <periodOfReport>2003-07-21</periodOfReport>


    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0000912219</issuerCik>
        <issuerName>FIDELITY BANCORP INC /DE/</issuerName>
        <issuerTradingSymbol>FBCI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001242965</rptOwnerCik>
            <rptOwnerName>BENTEL THOMAS E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>  </rptOwnerStreet1>
            <rptOwnerStreet2>  </rptOwnerStreet2>
            <rptOwnerCity>  </rptOwnerCity>
            <rptOwnerState>  </rptOwnerState>
            <rptOwnerZipCode>  </rptOwnerZipCode>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President &amp; Chief Op. Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeSecurity>
        <securityTitle>
            <value>Common Stock</value>
        </securityTitle>
        <transactionDate>
            <value>2003-07-21</value>
        </transactionDate>
        <transactionCoding>
            <transactionFormType>4</transactionFormType>
            <transactionCode>U</transactionCode>
            <equitySwapInvolved>0</equitySwapInvolved>
        </transactionCoding>
        <transactionTimeliness>
            <value></value>
        </transactionTimeliness>
        <transactionAmounts>
            <transactionShares>
                <value>42246</value>
            </transactionShares>
            <transactionValue>
                <value>0</value>
                <footnoteId id="F1"/>
            </transactionValue>
            <transactionAcquiredDisposedCode>
                <value>D</value>
            </transactionAcquiredDisposedCode>
        </transactionAmounts>
        <postTransactionAmounts>
            <sharesOwnedFollowingTransaction>
                <value>0</value>
            </sharesOwnedFollowingTransaction>
        </postTransactionAmounts>
        <ownershipNature>
            <directOrIndirectOwnership>
                <value>D</value>
            </directOrIndirectOwnership>
        </ownershipNature>
    </nonDerivativeSecurity>

    <derivativeSecurity>
        <securityTitle>
            <value>Stock Option</value>
        </securityTitle>
        <conversionOrExercisePrice>
            <value>6.6667</value>
        </conversionOrExercisePrice>
        <transactionDate>
            <value>2003-07-21</value>
        </transactionDate>
        <transactionCoding>
            <transactionFormType>4</transactionFormType>
            <transactionCode>U</transactionCode>
            <equitySwapInvolved>0</equitySwapInvolved>
        </transactionCoding>
        <transactionTimeliness>
            <value></value>
        </transactionTimeliness>
        <transactionAmounts>
            <transactionShares>
                <value>67608</value>
            </transactionShares>
            <transactionValue>
                <value>28.11</value>
            </transactionValue>
            <transactionAcquiredDisposedCode>
                <value>D</value>
            </transactionAcquiredDisposedCode>
        </transactionAmounts>
        <exerciseDate>
            <value>2003-07-21</value>
            <footnoteId id="F2"/>
        </exerciseDate>
        <expirationDate>
            <value>2003-12-15</value>
        </expirationDate>
        <underlyingSecurity>
            <underlyingSecurityTitle>
                <value>Common Stock</value>
            </underlyingSecurityTitle>
            <underlyingSecurityShares>
                <value>67608</value>
            </underlyingSecurityShares>
        </underlyingSecurity>
        <postTransactionAmounts>
            <sharesOwnedFollowingTransaction>
                <value>0</value>
            </sharesOwnedFollowingTransaction>
        </postTransactionAmounts>
        <ownershipNature>
            <directOrIndirectOwnership>
                <value>D</value>
            </directOrIndirectOwnership>
        </ownershipNature>
    </derivativeSecurity>

    <derivativeSecurity>
        <securityTitle>
            <value>Stock Option</value>
        </securityTitle>
        <conversionOrExercisePrice>
            <value>19.465</value>
        </conversionOrExercisePrice>
        <transactionDate>
            <value>2003-07-21</value>
        </transactionDate>
        <transactionCoding>
            <transactionFormType>4</transactionFormType>
            <transactionCode>U</transactionCode>
            <equitySwapInvolved>0</equitySwapInvolved>
        </transactionCoding>
        <transactionTimeliness>
            <value></value>
        </transactionTimeliness>
        <transactionAmounts>
            <transactionShares>
                <value>6000</value>
            </transactionShares>
            <transactionValue>
                <value>15.32</value>
            </transactionValue>
            <transactionAcquiredDisposedCode>
                <value>D</value>
            </transactionAcquiredDisposedCode>
        </transactionAmounts>
        <exerciseDate>
            <value>2003-07-21</value>
            <footnoteId id="F3"/>
        </exerciseDate>
        <expirationDate>
            <value>2012-03-29</value>
        </expirationDate>
        <underlyingSecurity>
            <underlyingSecurityTitle>
                <value>Common Stock</value>
            </underlyingSecurityTitle>
            <underlyingSecurityShares>
                <value>6000</value>
            </underlyingSecurityShares>
        </underlyingSecurity>
        <postTransactionAmounts>
            <sharesOwnedFollowingTransaction>
                <value>0</value>
            </sharesOwnedFollowingTransaction>
        </postTransactionAmounts>
        <ownershipNature>
            <directOrIndirectOwnership>
                <value>D</value>
            </directOrIndirectOwnership>
        </ownershipNature>
    </derivativeSecurity>

    <footnotes>
        <footnote id="F1">Disposed of pursuant to the Agreement and Plan of Reorganization between issuer and MAF Bancorp, Inc. (the &quot;Merger Agreement&quot;).  Pursuant to the Merger Agreement, the reporting person has the right to receive 0.89 shares of MAF Bancorp, Inc. common stock for each share of common stock of the issuer.  At the close of market on the effective date of the merger, MAF Bancorp, Inc. common stock had a market value of $39.30 per share.</footnote>
        <footnote id="F2">This option was cancelled in the merger in exchange for a cash payment of $1,900,765.12, representing the difference between the exercise price of the option and the market value of the underlying issuer common stock for purposes of calculating the cash payment of $34.78 per share.</footnote>
        <footnote id="F3">This option was cancelled in the merger in exchange for a cash payment of $91,897.20, representing the difference between the exercise price of the option and the market value of the underlying issuer common stock for purposes of calculating the cash payment of $34.78 per share.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Thomas E. Bentel</signatureName>
        <signatureDate>2003-07-23</signatureDate>
    </ownerSignature>

</ownershipDocument>

