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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 JIkPpZxiu5T3X49BMAue+bb13cMUWZtmbHF72nKq6NDiJM89XcE1lmTuFXmVWe8w
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<SEC-DOCUMENT>0001140361-10-025118.txt : 20100610
<SEC-HEADER>0001140361-10-025118.hdr.sgml : 20100610
<ACCEPTANCE-DATETIME>20100610164450
ACCESSION NUMBER:		0001140361-10-025118
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100604
FILED AS OF DATE:		20100610
DATE AS OF CHANGE:		20100610

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:			WETMORE DOUGLAS J
		CENTRAL INDEX KEY:			0001183718

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-06620
		FILM NUMBER:		10890772

	MAIL ADDRESS:	
		STREET 1:		C/O INTERNATIONAL FLAVORS & FRAGRANCES
		STREET 2:		521 WEST 57TH ST
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10019
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4/A
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2010-06-04</periodOfReport>

    <dateOfOriginalSubmission>2010-06-08</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001183718</rptOwnerCik>
            <rptOwnerName>WETMORE DOUGLAS J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>712 FIFTH AVENUE, 18TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10019</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Exec. VP and CFO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-06-04</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>11.0315</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>225000</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 purchased in multiple transactions at prices ranging from $11.00 to $11.06, 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 purchased at each separate price within the ranges set forth in this footnote (1) to this Form 4.</footnote>
        <footnote id="F2">Amendment to the Form 4 filed on June 8, 2010 has been filed to correct footnote (1).  Footnote (1) previously referred to the shares being &quot;sold&quot;, when in fact they were &quot;purchased&quot;.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Seth L. Kaplan, pursuant to power-of-attorney</signatureName>
        <signatureDate>2010-06-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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