<SEC-DOCUMENT>0000050725-16-000174.txt : 20161206
<SEC-HEADER>0000050725-16-000174.hdr.sgml : 20161206
<ACCEPTANCE-DATETIME>20161206161623
ACCESSION NUMBER:		0000050725-16-000174
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20161202
FILED AS OF DATE:		20161206
DATE AS OF CHANGE:		20161206

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			GRIFFON CORP
		CENTRAL INDEX KEY:			0000050725
		STANDARD INDUSTRIAL CLASSIFICATION:	METAL DOORS, SASH, FRAMES, MOLDING & TRIM [3442]
		IRS NUMBER:				111893410
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		712 FIFTH AVENUE
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10019
		BUSINESS PHONE:		2129575000

	MAIL ADDRESS:	
		STREET 1:		712 FIFTH AVENUE
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10019

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INSTRUMENT SYSTEMS CORP /DE/
		DATE OF NAME CHANGE:	19920703

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ALPERT HENRY A
		CENTRAL INDEX KEY:			0001208677

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-06620
		FILM NUMBER:		162036484
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_148105896867792.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2016-12-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000050725</issuerCik>
        <issuerName>GRIFFON CORP</issuerName>
        <issuerTradingSymbol>GFF</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001208677</rptOwnerCik>
            <rptOwnerName>ALPERT HENRY A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O GRIFFON CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>712 FIFTH AVENUE, 18TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10019</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2016-12-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>14980</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>23.55</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>51552</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The price reported in Column 4 is a weighted average price.  These shares were disposed of in multiple transactions at prices ranging from $23.40 to $23.675, inclusive.  The reporting person undertakes to provide Griffon Corporation, any security holder of Griffon Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares disposed of at each price within the range set forth in this footnote.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Seth L. Kaplan, as attorney-in-fact</signatureName>
        <signatureDate>2016-12-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
