<SEC-DOCUMENT>0001140361-15-000833.txt : 20150106
<SEC-HEADER>0001140361-15-000833.hdr.sgml : 20150106
<ACCEPTANCE-DATETIME>20150106173759
ACCESSION NUMBER:		0001140361-15-000833
CONFORMED SUBMISSION TYPE:	5
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20141231
FILED AS OF DATE:		20150106
DATE AS OF CHANGE:		20150106

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NN INC
		CENTRAL INDEX KEY:			0000918541
		STANDARD INDUSTRIAL CLASSIFICATION:	BALL & ROLLER BEARINGS [3562]
		IRS NUMBER:				621096725
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2000 WATERS EDGE DR
		CITY:			JOHNSON CITY
		STATE:			TN
		ZIP:			37604
		BUSINESS PHONE:		4237439151

	MAIL ADDRESS:	
		STREET 1:		2000 WATERS EDGE DR
		CITY:			JOHNSON CITY
		STATE:			TN
		ZIP:			37604

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	NN BALL & ROLLER INC
		DATE OF NAME CHANGE:	19940203

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			KELLY WILLIAM C JR
		CENTRAL INDEX KEY:			0001196831

	FILING VALUES:
		FORM TYPE:		5
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-23486
		FILM NUMBER:		15511216
</SEC-HEADER>
<DOCUMENT>
<TYPE>5
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 5
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>5</documentType>

    <periodOfReport>2014-12-31</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <form3HoldingsReported>0</form3HoldingsReported>

    <form4TransactionsReported>0</form4TransactionsReported>

    <issuer>
        <issuerCik>0000918541</issuerCik>
        <issuerName>NN INC</issuerName>
        <issuerTradingSymbol>NNBR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001196831</rptOwnerCik>
            <rptOwnerName>KELLY WILLIAM C JR</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2000 WATERS EDGE DR.</rptOwnerStreet1>
            <rptOwnerStreet2>BUILDING C, SUITE 12</rptOwnerStreet2>
            <rptOwnerCity>JOHNSON CITY</rptOwnerCity>
            <rptOwnerState>TN</rptOwnerState>
            <rptOwnerZipCode>37604</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP, Chief Adm. Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2014-07-09</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>W</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>160</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>29559</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ William C. Kelly, Jr.</signatureName>
        <signatureDate>2015-01-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
