<SEC-DOCUMENT>0000764065-16-000291.txt : 20161027
<SEC-HEADER>0000764065-16-000291.hdr.sgml : 20161027
<ACCEPTANCE-DATETIME>20161027172228
ACCESSION NUMBER:		0000764065-16-000291
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20161025
FILED AS OF DATE:		20161027
DATE AS OF CHANGE:		20161027

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CLIFFS NATURAL RESOURCES INC.
		CENTRAL INDEX KEY:			0000764065
		STANDARD INDUSTRIAL CLASSIFICATION:	METAL MINING [1000]
		IRS NUMBER:				341464672
		STATE OF INCORPORATION:			OH
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		200 PUBLIC SQUARE
		STREET 2:		STE. 3300
		CITY:			CLEVELAND
		STATE:			OH
		ZIP:			44114-2315
		BUSINESS PHONE:		216-694-5700

	MAIL ADDRESS:	
		STREET 1:		200 PUBLIC SQUARE
		STREET 2:		STE. 3300
		CITY:			CLEVELAND
		STATE:			OH
		ZIP:			44114-2315

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	CLEVELAND CLIFFS INC
		DATE OF NAME CHANGE:	19920703

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Rychel Eric M
		CENTRAL INDEX KEY:			0001688357

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-08944
		FILM NUMBER:		161956379

	MAIL ADDRESS:	
		STREET 1:		200 PUBLIC SQUARE, SUITE 3300
		CITY:			CLEVELAND
		STATE:			OH
		ZIP:			44114
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_147760333512651.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2016-10-25</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000764065</issuerCik>
        <issuerName>CLIFFS NATURAL RESOURCES INC.</issuerName>
        <issuerTradingSymbol>CLF</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001688357</rptOwnerCik>
            <rptOwnerName>Rychel Eric M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>200 PUBLIC SQUARE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 3300</rptOwnerStreet2>
            <rptOwnerCity>CLEVELAND</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>44114</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 Shares</value>
            </securityTitle>
            <transactionDate>
                <value>2016-10-25</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>6845</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6845</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Reflects the number of restricted shares granted to the Reporting Person as the 2016 Director Restricted Shares upon the Reporting Person's election to the Board of Directors pursuant to the Amended and Restated 2014 Nonemployee Directors' Compensation Plan.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ James D. Graham by Power of Attorney</signatureName>
        <signatureDate>2016-10-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
