-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 WO9imv67At+D6jq8gqN/z1bzvF5peqrGH9XOE7x0NRhf7DMOpAz5CLghIY6+B/wY
 RQCixytVu1NP4SzPkt4dwQ==

<SEC-DOCUMENT>0001179110-03-004368.txt : 20030729
<SEC-HEADER>0001179110-03-004368.hdr.sgml : 20030729
<ACCEPTANCE-DATETIME>20030729151937
ACCESSION NUMBER:		0001179110-03-004368
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20030729
FILED AS OF DATE:		20030729

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			TCW CONVERTIBLE SECURITIES FUND INC
		CENTRAL INDEX KEY:			0000809559
		IRS NUMBER:				930939398
		STATE OF INCORPORATION:			MD
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		865 S FIGUEROA ST STE 1800
		CITY:			LOS ANGELES
		STATE:			CA
		ZIP:			90071
		BUSINESS PHONE:		2132440000

	MAIL ADDRESS:	
		STREET 1:		865 S. FIGUEROA STREET,
		STREET 2:		SUITE 1800
		CITY:			LOSANGELES
		STATE:			CA
		ZIP:			90017

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LYON THOMAS D
		CENTRAL INDEX KEY:			0001118968

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	811-04980
		FILM NUMBER:		03808545

	BUSINESS ADDRESS:	
		STREET 1:		865 S. FIGUEROA STREET
		STREET 2:		SUITE 1800
		CITY:			LOS ANGELES
		STATE:			CA
		ZIP:			90017
		BUSINESS PHONE:		2132440073

	MAIL ADDRESS:	
		STREET 1:		865 S. FIGUEROA STREET
		STREET 2:		SUITE 1800
		CITY:			LOS ANGELES
		STATE:			CA
		ZIP:			90017
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<ownershipDocument>
    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>
<periodOfReport>2003-07-29</periodOfReport>
<notSubjectToSection16>0</notSubjectToSection16>
    <issuer>
        <issuerCik>0000809559</issuerCik>
        <issuerName>TCW CONVERTIBLE SECURITIES FUND INC</issuerName>
        <issuerTradingSymbol>CVT</issuerTradingSymbol>
</issuer>
<reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001118968</rptOwnerCik>
            <rptOwnerName>LYON THOMAS D</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>TCW CONVERTIBLE SECURITIES FUND, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>865 S. FIGUEROA ST., STE. 1800</rptOwnerStreet2>
            <rptOwnerCity>LOS ANGELES</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>90017</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
<isDirector>0</isDirector>
<isOfficer>1</isOfficer>
<isTenPercentOwner>0</isTenPercentOwner>
<isOther>0</isOther>
<officerTitle>Senior V.P.</officerTitle>
<otherText></otherText>
</reportingOwnerRelationship>
</reportingOwner>
<nonDerivativeTable><nonDerivativeTransaction><securityTitle><value>Common Stock</value>
</securityTitle>
<transactionDate><value>2003-07-29</value>
</transactionDate>
<transactionCoding><transactionFormType>4</transactionFormType>
<transactionCode>P</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved>
</transactionCoding>
<transactionAmounts><transactionShares><value>5000</value>
</transactionShares>
<transactionPricePerShare><value>4.4526</value>
</transactionPricePerShare>
<transactionAcquiredDisposedCode><value>A</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts><sharesOwnedFollowingTransaction><value>12500</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature><directOrIndirectOwnership><value>D</value>
</directOrIndirectOwnership>
</ownershipNature>
</nonDerivativeTransaction>
<nonDerivativeTransaction><securityTitle><value>Common Stock</value>
</securityTitle>
<transactionDate><value>2003-07-29</value>
</transactionDate>
<transactionCoding><transactionFormType>4</transactionFormType>
<transactionCode>P</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved>
</transactionCoding>
<transactionAmounts><transactionShares><value>750</value>
</transactionShares>
<transactionPricePerShare><value>4.46</value>
</transactionPricePerShare>
<transactionAcquiredDisposedCode><value>A</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts><sharesOwnedFollowingTransaction><value>13250</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature><directOrIndirectOwnership><value>I</value>
</directOrIndirectOwnership>
<natureOfOwnership><value>See Footnote</value>
<footnoteId id="F1"></footnoteId>
</natureOfOwnership>
</ownershipNature>
</nonDerivativeTransaction>
<nonDerivativeTransaction><securityTitle><value>Common Stock</value>
</securityTitle>
<transactionDate><value>2003-07-29</value>
</transactionDate>
<transactionCoding><transactionFormType>4</transactionFormType>
<transactionCode>P</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved>
</transactionCoding>
<transactionAmounts><transactionShares><value>750</value>
</transactionShares>
<transactionPricePerShare><value>4.46</value>
</transactionPricePerShare>
<transactionAcquiredDisposedCode><value>A</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts><sharesOwnedFollowingTransaction><value>14000</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature><directOrIndirectOwnership><value>I</value>
</directOrIndirectOwnership>
<natureOfOwnership><value>See Footnote</value>
<footnoteId id="F2"></footnoteId>
</natureOfOwnership>
</ownershipNature>
</nonDerivativeTransaction>
<nonDerivativeTransaction><securityTitle><value>Common Stock</value>
</securityTitle>
<transactionDate><value>2003-07-29</value>
</transactionDate>
<transactionCoding><transactionFormType>4</transactionFormType>
<transactionCode>P</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved>
</transactionCoding>
<transactionAmounts><transactionShares><value>685</value>
</transactionShares>
<transactionPricePerShare><value>4.44</value>
</transactionPricePerShare>
<transactionAcquiredDisposedCode><value>A</value>
</transactionAcquiredDisposedCode>
</transactionAmounts>
<postTransactionAmounts><sharesOwnedFollowingTransaction><value>14685</value>
</sharesOwnedFollowingTransaction>
</postTransactionAmounts>
<ownershipNature><directOrIndirectOwnership><value>D</value>
</directOrIndirectOwnership>
</ownershipNature>
</nonDerivativeTransaction>
</nonDerivativeTable>
<footnotes><footnote id="F1">Purchased for Kathryn E. Lyon (Minor Daughter)</footnote>
<footnote id="F2">Purchased for James D. Lyon (Minor Son)</footnote>
</footnotes>
<ownerSignature><signatureName>Philip K. Holl for Thomas D. Lyon by Power of Attorney dated August 20, 2002</signatureName>
<signatureDate>2003-07-29</signatureDate>
</ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----