<SEC-DOCUMENT>0001209191-20-061011.txt : 20201202
<SEC-HEADER>0001209191-20-061011.hdr.sgml : 20201202
<ACCEPTANCE-DATETIME>20201202070007
ACCESSION NUMBER:		0001209191-20-061011
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20201130
FILED AS OF DATE:		20201202
DATE AS OF CHANGE:		20201202

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			HEDRICK MARC H
		CENTRAL INDEX KEY:			0001203672

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34375
		FILM NUMBER:		201362381

	MAIL ADDRESS:	
		STREET 1:		C/O CYTORI THERAPEUTICS, INC.
		STREET 2:		3020 CALLAN ROAD
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92121

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			PLUS THERAPEUTICS, INC.
		CENTRAL INDEX KEY:			0001095981
		STANDARD INDUSTRIAL CLASSIFICATION:	SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
		IRS NUMBER:				330827593
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		4200 MARATHON BLVD.
		STREET 2:		SUITE 200
		CITY:			AUSTIN
		STATE:			TX
		ZIP:			78756
		BUSINESS PHONE:		737.255.7194

	MAIL ADDRESS:	
		STREET 1:		4200 MARATHON BLVD.
		STREET 2:		SUITE 200
		CITY:			AUSTIN
		STATE:			TX
		ZIP:			78756

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	CYTORI THERAPEUTICS, INC.
		DATE OF NAME CHANGE:	20050712

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MACROPORE INC
		DATE OF NAME CHANGE:	20010320
</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>2020-11-30</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001095981</issuerCik>
        <issuerName>PLUS THERAPEUTICS, INC.</issuerName>
        <issuerTradingSymbol>PSTV</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001203672</rptOwnerCik>
            <rptOwnerName>HEDRICK MARC H</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O PLUS THERAPEUTICS INC.</rptOwnerStreet1>
            <rptOwnerStreet2>4200 MARATHON BOULEVARD, SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>AUSTIN</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>78756</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Executive Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2020-11-30</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2200</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>2.14</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>11367</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <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 $2.13 to $2.15 per share. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer 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 range set forth in this footnote.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Andrew Sims, as attorney-in-fact</signatureName>
        <signatureDate>2020-12-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
