<SEC-DOCUMENT>0001140361-15-018898.txt : 20150511
<SEC-HEADER>0001140361-15-018898.hdr.sgml : 20150511
<ACCEPTANCE-DATETIME>20150511185914
ACCESSION NUMBER:		0001140361-15-018898
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20150319
FILED AS OF DATE:		20150511
DATE AS OF CHANGE:		20150511

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:		207 MOCKINGBIRD LANE
		CITY:			JOHNSON CITY
		STATE:			TN
		ZIP:			37604
		BUSINESS PHONE:		4237439151

	MAIL ADDRESS:	
		STREET 1:		207 MOCKINGBIRD LANE
		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:			MORRIS G RONALD
		CENTRAL INDEX KEY:			0001196829

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-23486
		FILM NUMBER:		15852360
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4/A
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2015-03-19</periodOfReport>

    <dateOfOriginalSubmission>2015-03-23</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001196829</rptOwnerCik>
            <rptOwnerName>MORRIS G RONALD</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>207 MOCKINGBIRD LANE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>JOHNSON CITY</rptOwnerCity>
            <rptOwnerState>TN</rptOwnerState>
            <rptOwnerZipCode>37604</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>2015-03-19</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>4800</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>70400</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">The reporting person filed Amendment No. 1 to Form 4 on March 25, 2015 (&quot;Amendment No. 1&quot;), which amended the reporting person's Form 4 filed on March 23, 2015 (the &quot;Original Form 4&quot;).  Amendment No. 1 was filed to report a grant of 1,000 shares of restricted stock (the &quot;Omitted Shares&quot;), which grant was inadvertently omitted from the Original Form 4.  Amendment No. 1 incorrectly reported that the Omitted Shares vest over a period of three years in equal annual installments beginning on March 19, 2016.  This Amendment No. 2 further amends the Original Form 4 to correctly report that the Omitted Shares and all of the remaining 3,800 shares of restricted stock granted to the reporting person on March 19, 2015 vest on March 19, 2016.  The shares reported in Column 5 of Table I represent the shares owned by the reporting person as of March 19, 2015.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ William C. Kelly, Jr. by Power of Attorney</signatureName>
        <signatureDate>2015-05-11</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
