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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-03-05</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000101295</issuerCik>
        <issuerName>UNITED GUARDIAN INC</issuerName>
        <issuerTradingSymbol>UG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000943504</rptOwnerCik>
            <rptOwnerName>GLOBUS KENNETH H</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O UNITED-GUARDIAN, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>230 MARCUS BLVD., P.O. BOX 18050</rptOwnerStreet2>
            <rptOwnerCity>HAUPPAUGE</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>11788</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2020-03-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>8000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1334853</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>SEE FOOTNOTE #3</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Reporting Person owns UG stock both directly and indirectly. After the transfer of the 8,000 shares being gifted as indicated in this Form 4, Direct ownership is 287,427, and Indirect ownership is 1,047,426 shares. Of the Indirect ownership, 287,426 shares are owned by Reporting Person's wife, and 760,000 shares are under the control of the Reporting Person in his role as co-Trustee of the Alfred R. Globus Testamentary
Trust, the owner of those shares.</footnote>
        <footnote id="F2">In Field 6 Reporting Person indicated that his ownership is &quot;Indirect&quot;, but that is only because there is no option to state ownership as both &quot;Direct&quot; AND &quot;Indirect&quot;. The majority of Reporting Person's ownership is based on beneficial ownership of UG stock owned both by his wife and by the Alfred R. Globus Testamentary Trust, of which he is a Trustee and has sole voting rights. Reporting Person's Direct and and Indirect ownership is detailed in Footnote #1.</footnote>
        <footnote id="F3">287,426 shares are owned by Reporting Person's wife, and 760,000 shares are owned by the Alfred R. Globus Testamentary Trust, of which the Reporting Person is a Trustee and has sole voting rights.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/S/ Ken Globus</signatureName>
        <signatureDate>2020-03-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
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X0306
4
2020-03-05
0
0000101295
UNITED GUARDIAN INC
UG
0000943504
GLOBUS KENNETH H
C/O UNITED-GUARDIAN, INC.
230 MARCUS BLVD., P.O. BOX 18050
HAUPPAUGE
NY
11788
1
1
1
0
President
Common Stock
2020-03-05
4
G
0
8000
0
D
1334853
I
SEE FOOTNOTE #3
Reporting Person owns UG stock both directly and indirectly. After the transfer of the 8,000 shares being gifted as indicated in this Form 4, Direct ownership is 287,427, and Indirect ownership is 1,047,426 shares. Of the Indirect ownership, 287,426 shares are owned by Reporting Person's wife, and 760,000 shares are under the control of the Reporting Person in his role as co-Trustee of the Alfred R. Globus Testamentary
Trust, the owner of those shares.
In Field 6 Reporting Person indicated that his ownership is "Indirect", but that is only because there is no option to state ownership as both "Direct" AND "Indirect". The majority of Reporting Person's ownership is based on beneficial ownership of UG stock owned both by his wife and by the Alfred R. Globus Testamentary Trust, of which he is a Trustee and has sole voting rights. Reporting Person's Direct and and Indirect ownership is detailed in Footnote #1.
287,426 shares are owned by Reporting Person's wife, and 760,000 shares are owned by the Alfred R. Globus Testamentary Trust, of which the Reporting Person is a Trustee and has sole voting rights.
/S/ Ken Globus
2020-03-06