<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-07-30</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001863294</issuerCik>
        <issuerName>DA32 Life Science Tech Acquisition Corp.</issuerName>
        <issuerTradingSymbol>DALS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001009258</rptOwnerCik>
            <rptOwnerName>DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C)</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1></rptOwnerStreet1>
            <rptOwnerStreet2>345 PARK AVENUE SOUTH, 12TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10010</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>Director by Deputization</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001010823</rptOwnerCik>
            <rptOwnerName>Deerfield Mgmt L.P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>345 PARK AVENUE SOUTH, 12TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState></rptOwnerState>
            <rptOwnerZipCode></rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>Director by deputization</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001301041</rptOwnerCik>
            <rptOwnerName>DEERFIELD PARTNERS, L.P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>345 PARK AVENUE SOUTH, 12TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10010</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>Director by deputization</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001352546</rptOwnerCik>
            <rptOwnerName>Flynn James E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>345 PARK AVENUE SOUTH, 12TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10010</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>Director by deputization</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-07-30</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1600000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>10.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1600000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Through Deerfield Partners, L.P.</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-07-30</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F3"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>650000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>10.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2250000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Through DA32 Sponsor LLC</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Deerfield Partners, L.P. purchased 1,600,000 shares of the Issuer's Class A common stock for $10.00 per share in the Issuer's initial public offering.</footnote>
        <footnote id="F2">This Form 4 is filed jointly by Deerfield Partners, L.P. (&quot;Deerfield Partners&quot;), Deerfield Mgmt, L.P. (&quot;Deerfield Mgmt&quot;), Deerfield Management Company, L.P. (Deerfield Management&quot;) and James E. Flynn (collectively, the &quot;Reporting Persons&quot;). Each of the Reporting Persons is a member of a Section 13(d) group. Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein except to the extent of his or its pecuniary interest therein.</footnote>
        <footnote id="F3">DA32 Sponsor LLC (&quot;Sponsor&quot;) purchased 650,000 shares of Class A common stock from the Issuer in a private placement conducted by the Issuer concurrently with its initial public offering. Such shares constitute &quot;private placement shares&quot; as such term is defined in the Issuer's Registration Statement on Form S-1 (File No. 333-257679).  The purchase of such shares was exempted from Section 16(b) under the Securities Exchange Act of 1934, as amended (the &quot;Exchange Act&quot;), pursuant to Rule 16b-3(d) under the Exchange Act</footnote>
        <footnote id="F4">Sponsor is the record holder of the securities reported herein. As one of three managing members of Sponsor, Deerfield Partners may be deemed to beneficially own the securities owned directly by Sponsor. As the general partner of Deerfield Partners, Deerfield Mgmt may be deemed to beneficially own the securities owned directly by Sponsor. As the investment manager of Deerfield Partners, Deerfield Management may be deemed to beneficially own securities owned directly by Sponsor. As the sole member of the general partner of each of Deerfield Management and Deerfield Mgmt, James E. Flynn may be deemed to beneficially own the securities owned directly by Sponsor. The Sponsor and other members of the Sponsor are separately filing a Form 4 with respect to the securities reported herein.</footnote>
    </footnotes>

    <remarks>Andrew ElBardissi, an employee of Deerfield Management Company, serves as a director of the Issuer. See Exhibit 99.1 - Joint Filer Information, which is incorporated herein by reference and describes in further detail the relationships of the Reporting Persons to the Issuer. Exhibit 24 - Power of Attorney</remarks>

    <ownerSignature>
        <signatureName>/s/ Jonathan Isler, Attorney-in-Fact for Deerfield Management Company, L.P.</signatureName>
        <signatureDate>2021-08-03</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Jonathan Isler, Attorney-in-Fact for Deerfield Partners, L.P.</signatureName>
        <signatureDate>2021-08-03</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Jonathan Isler, Attorney-in-Fact for Deerfield Mgmt, L.P.</signatureName>
        <signatureDate>2021-08-03</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Jonathan Isler, Attorney-in-Fact for Deerfield James E. Flynn</signatureName>
        <signatureDate>2021-08-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
