<SEC-DOCUMENT>0001209191-23-003594.txt : 20230117
<SEC-HEADER>0001209191-23-003594.hdr.sgml : 20230117
<ACCEPTANCE-DATETIME>20230117191008
ACCESSION NUMBER:		0001209191-23-003594
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20230113
FILED AS OF DATE:		20230117
DATE AS OF CHANGE:		20230117

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Corbett Ryan
		CENTRAL INDEX KEY:			0001831686

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-39277
		FILM NUMBER:		23532568

	MAIL ADDRESS:	
		STREET 1:		6720 VIA AUSTI PARKWAY
		STREET 2:		SUITE 450
		CITY:			LAS VEGAS
		STATE:			NV
		ZIP:			89119

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MP Materials Corp. / DE
		CENTRAL INDEX KEY:			0001801368
		STANDARD INDUSTRIAL CLASSIFICATION:	METAL MINING [1000]
		IRS NUMBER:				844465489
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1700 S. PAVILION CENTER DR.
		STREET 2:		SUITE 800
		CITY:			LAS VEGAS
		STATE:			NV
		ZIP:			89135
		BUSINESS PHONE:		(702) 844-6111

	MAIL ADDRESS:	
		STREET 1:		1700 S. PAVILION CENTER DR.
		STREET 2:		SUITE 800
		CITY:			LAS VEGAS
		STATE:			NV
		ZIP:			89135

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Fortress Value Acquisition Corp.
		DATE OF NAME CHANGE:	20200128
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2023-01-13</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001801368</issuerCik>
        <issuerName>MP Materials Corp. / DE</issuerName>
        <issuerTradingSymbol>MP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001831686</rptOwnerCik>
            <rptOwnerName>Corbett Ryan</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1700 S. PAVILION CENTER DRIVE, SUITE 800</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LAS VEGAS</rptOwnerCity>
            <rptOwnerState>NV</rptOwnerState>
            <rptOwnerZipCode>89135</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Financial Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2023-01-13</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>16931</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>228407</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2023-01-14</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2410</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>29.53</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>225997</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The securities reported are restricted stock units that vest in four annual installments beginning on the first anniversary of the grant date. Each restricted stock unit represents the contingent right to receive, upon vesting of the unit, one share of the issuer's Class A common stock.</footnote>
        <footnote id="F2">Represents shares withheld to satisfy tax withholding obligation applicable to the vesting of 8,919 restricted stock units that vested on January 14, 2023.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Elliot D. Hoops, Attorney-In-Fact for Ryan Corbett</signatureName>
        <signatureDate>2023-01-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
