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

    <schemaVersion>X0305</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2012-03-26</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000880117</issuerCik>
        <issuerName>SANFILIPPO JOHN B &amp; SON INC</issuerName>
        <issuerTradingSymbol>JBSS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000935378</rptOwnerCik>
            <rptOwnerName>SANFILIPPO JASPER B</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1703 N. RANDALL ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>ELGIN</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60123-7820</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000906043</rptOwnerCik>
            <rptOwnerName>SANFILIPPO MARIAN</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1703 N. RANDALL ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>ELGIN</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60123-7820</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>Member of 13(d) Group</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A - Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2012-03-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>22480</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>11.14</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>22480</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F4"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A - Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2012-03-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>32609</value>
                    <footnoteId id="F5"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>130436</value>
                    <footnoteId id="F6"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>As Trustee of Family Trusts</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A - Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2012-03-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>8152</value>
                    <footnoteId id="F7"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>11.14</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8152</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F8"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A - Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2012-03-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>44044</value>
                    <footnoteId id="F9"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>176176</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>As Co-Trustee of Family Trusts</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A - Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2012-03-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5531</value>
                    <footnoteId id="F10"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>11.14</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>181707</value>
                    <footnoteId id="F11"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>As Co-Trustee of Family Trusts</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Jasper B. Sanfilippo purchased the shares of Class A Common Stock listed herein pursuant to a written agreement between James J. Sanfilippo and Jasper B. Sanfilippo, among others.  Under the agreement, Jasper B. Sanfilippo purchased shares of Class A Common Stock of John B. Sanfilippo &amp; Son, Inc. (the Company) equal to the number of shares of Common Stock of the Company sold by Jasper B. Sanfilippo in an earlier sale.</footnote>
        <footnote id="F2">The purchase price for each share of Class A Common Stock is $11.14.  This represents the highest price received by any of Jasper B. Sanfilippo, Marian R. Sanfilippo, Jeffrey T. Sanfilippo, John E. Sanfilippo and the Jasper B. Sanfilippo, Jr. Irrevocable Trust, dated October 6, 2006, for the sales of Common Stock of the Company as previously reported by each of the above individuals.</footnote>
        <footnote id="F3">As a result of the transactions described herein, the reporting persons will own the same number of shares of common equity (defined as the total combined number of shares of Class A Common Stock and Common Stock) of the Company as owned prior to this filing.</footnote>
        <footnote id="F4">Shares held by Jasper B. Sanfilippo.</footnote>
        <footnote id="F5">The shares are no longer beneficially owned by Jasper B. Sanfilippo as a result of the dissolution of the James J. Sanfilippo Trust, dated September 26, 1991 for which Jasper B. Sanfilippo was the sole Trustee.</footnote>
        <footnote id="F6">The shares are held in the name of the following trusts:  Jasper B. Sanfilippo, Jr. Trust, dated September 23, 1991, Lisa Ann Sanfilippo Trust, dated October 4, 1991, Jeffrey T. Sanfilippo Trust, dated October 4, 1991 and John E. Sanfilippo Trust, dated October 2, 1991.  Each trust listed above holds 32,609 shares of Class A Common Stock and Jasper B. Sanfilippo is sole Trustee of each of the above Trusts.</footnote>
        <footnote id="F7">Marian R. Sanfilippo purchased the shares of Class A Common Stock listed herein pursuant to a written agreement between James J. Sanfilippo and Marian R. Sanfilippo, among others.  Under the agreement, Marian R. Sanfilippo purchased shares of Class A Common Stock of John B. Sanfilippo &amp; Son, Inc. (the Company) equal to the number of shares of Common Stock of the Company sold by Marian R. Sanfilippo in an earlier sale.</footnote>
        <footnote id="F8">Shares held by Marian R. Sanfilippo.</footnote>
        <footnote id="F9">The shares are no longer beneficially owned by Marian R. Sanfilippo as a result of the dissolution of the James J. Sanfilippo Irrevocable Trust dated October 6, 2006 for which Marian R. Sanfilippo was a Co-Trustee.</footnote>
        <footnote id="F10">Class A Common Stock purchased by the Jasper B. Sanfilippo Irrevocable Trust dated October 6, 2006 pursuant to a written agreement between James J. Sanfilippo and Marian R. Sanfilippo as Co-Trustee, among others.  Under the agreement, the Jasper B. Sanfilippo Irrevocable Trust dated October 6, 2006 purchased shares of Class A Common Stock of John B. Sanfilippo &amp; Son, Inc. (the Company) equal to the number of shares of Common Stock of the Company sold by Marian R. Sanfilippo as a Co-Trustee of the Jasper B. Sanfilippo Irrevocable Trust dated October 6, 2006.</footnote>
        <footnote id="F11">The shares are held in the name of the following trusts: Jeffrey T. Sanfilippo Irrevocable Trust, dated October 6, 2006, Jasper B. Sanfilippo, Jr. Irrevocable Trust, dated October 6, 2006, John E. Sanfilippo Irrevocable Trust, dated October 6, 2006 and Lisa A. Evon Irrevocable Trust, dated October 6, 2006.  Each Trust listed above holds 44,044 shares of Class A Common Stock, with the exception of the Jasper B. Sanfilippo, Jr. Irrevocable Trust, dated October 6, 2006, which holds 49,575 shares of Class A Common Stock.  Marian Sanfilippo is a Co-Trustee of each of the above Trusts.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/Herbert J. Marros as Power of Attorney</signatureName>
        <signatureDate>2012-03-28</signatureDate>
    </ownerSignature>
</ownershipDocument>
