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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 Fi9JxwzMdLDsKX9JadQNX7mOD70YvaJBi6Hu09gnRNVPYVHZ9TGw3Dtj0R5MCDZJ
 QmP1pKGTN8M3FnPUEW34qw==

<SEC-DOCUMENT>0000009521-04-000004.txt : 20040105
<SEC-HEADER>0000009521-04-000004.hdr.sgml : 20040105
<ACCEPTANCE-DATETIME>20040105153856
ACCESSION NUMBER:		0000009521-04-000004
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20031231
FILED AS OF DATE:		20040105

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			DINSMORE THOMAS H
		CENTRAL INDEX KEY:			0001190030

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	811-02151
		FILM NUMBER:		04504626

	MAIL ADDRESS:	
		STREET 1:		C/O DAVIS-DINSMORE MANAGEMENT
		STREET 2:		65 MADISON AVE
		CITY:			MORRISTOWN
		STATE:			NJ
		ZIP:			07960

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BANCROFT CONVERTIBLE FUND INC
		CENTRAL INDEX KEY:			0000009521
		STANDARD INDUSTRIAL CLASSIFICATION:	UNKNOWN SIC - 0000 [0000]
		IRS NUMBER:				042476994
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1031

	BUSINESS ADDRESS:	
		STREET 1:		65 MADISON AVENUE
		STREET 2:		SUITE 550
		CITY:			MORRISTOWN
		STATE:			NJ
		ZIP:			07960
		BUSINESS PHONE:		(973) 631-1177

	MAIL ADDRESS:	
		STREET 1:		65 MADISON AVENUE
		STREET 2:		SUITE 550
		CITY:			MORRISTOWN
		STATE:			NJ
		ZIP:			07960
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>

<ownershipDocument>

    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2003-12-31</periodOfReport>


    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000009521</issuerCik>
        <issuerName>BANCROFT CONVERTIBLE FUND INC</issuerName>
        <issuerTradingSymbol>BCV</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001190030</rptOwnerCik>
            <rptOwnerName>DINSMORE THOMAS H</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O DAVIS-DINSMORE MANAGEMENT</rptOwnerStreet1>
            <rptOwnerStreet2>65 MADISON AVE</rptOwnerStreet2>
            <rptOwnerCity>MORRISTOWN</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07960</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>

        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2003-12-31</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>200</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>17.82</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6973</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F4"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>

    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">These shares were acquired in the Fund's 2003 Rights Offering pursuant to the Over-Subscription Privilege.  Only shareholders who subscribed for all shares allocated to them in the Primary Subscription were able to participate in the Over-Subscription Privilege.  The 2003 Rights Offering was approved by the Fund's Board of Directors.</footnote>
        <footnote id="F2">Based on the subscription price per share of 95% of the average of the volume-weighted average sales prices of a share of the Fund's Common Stock on the American Stock Exchange (&quot;AMEX&quot;) on December 17, 2003 and the four preceding trading days.</footnote>
        <footnote id="F3">Includes 53 shares acquired on December 26, 2003 under the BCV dividend reinvestment plan.</footnote>
        <footnote id="F4">In addition, the reporting person is the indirect beneficial owner of 8,194 additional shares. These additional shares consist of:

(i) 3,383 shares owned by his wife, which the reporting person disclaims beneficial ownership of. This report shall not be deemed an admission that the reporting person is the beneficial owner of the securities for purposes of Section 16 or for any other purpose. Includes 34 shares acquired on December 26, 2003 under the BCV dividend reinvestment plan,

(ii) 2,350 shares held by a Uniform Transfer to Minors Act NJ (UTMA) trust for his son's benefit, and

(iii) 2,461 shares held by an UTMA trust for his daughter's benefit. Includes 23 shares acquired on December 26, 2003 under the BCV dividend reinvestment plan.</footnote>
    </footnotes>


    <ownerSignature>
        <signatureName>/s/ Gary I. Levine, attorney-in-fact</signatureName>
        <signatureDate>2004-01-05</signatureDate>
    </ownerSignature>

</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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