<SEC-DOCUMENT>0000017313-20-000038.txt : 20200323
<SEC-HEADER>0000017313-20-000038.hdr.sgml : 20200323
<ACCEPTANCE-DATETIME>20200323160525
ACCESSION NUMBER:		0000017313-20-000038
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200320
FILED AS OF DATE:		20200323
DATE AS OF CHANGE:		20200323

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			DIEHL BOWEN S
		CENTRAL INDEX KEY:			0001602998

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	814-00061
		FILM NUMBER:		20734957

	MAIL ADDRESS:	
		STREET 1:		12900 PRESTON ROAD
		STREET 2:		SUITE 700
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75230

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CAPITAL SOUTHWEST CORP
		CENTRAL INDEX KEY:			0000017313
		IRS NUMBER:				751072796
		STATE OF INCORPORATION:			TX
		FISCAL YEAR END:			0331

	BUSINESS ADDRESS:	
		STREET 1:		5400 LYNDON B. JOHNSON FREEWAY
		STREET 2:		SUITE 1300
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75240
		BUSINESS PHONE:		2142385700

	MAIL ADDRESS:	
		STREET 1:		5400 LYNDON B. JOHNSON FREEWAY
		STREET 2:		SUITE 1300
		CITY:			DALLAS
		STATE:			TX
		ZIP:			75240
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_158499390771928.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-03-20</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000017313</issuerCik>
        <issuerName>CAPITAL SOUTHWEST CORP</issuerName>
        <issuerTradingSymbol>CSWC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001602998</rptOwnerCik>
            <rptOwnerName>DIEHL BOWEN S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O CAPITAL SOUTHWEST CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>5400 LYNDON B. JOHNSON FWY, SUITE 1300</rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75240</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President and CEO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2020-03-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>20000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>9.46</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>308353</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By PHC Investments, LLC</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>94942</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">In connection with the vesting of the restricted stock awards directly held by the reporting person, the reporting person transferred such shares to PHC Investments, LLC. PHC Investments, LLC is fifty percent owned by the reporting person and fifty percent owned by his spouse.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Bowen S. Diehl</signatureName>
        <signatureDate>2020-03-23</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
