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        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001677940</identifier>
        </entity>
        <period>
            <startDate>2026-06-04</startDate>
            <endDate>2026-06-04</endDate>
        </period>
    </context>
    <dei:AmendmentFlag contextRef="AsOf2026-06-04" id="Fact000003">true</dei:AmendmentFlag>
    <dei:EntityCentralIndexKey contextRef="AsOf2026-06-04" id="Fact000004">0001677940</dei:EntityCentralIndexKey>
    <dei:DocumentType contextRef="AsOf2026-06-04" id="Fact000009">8-K/A</dei:DocumentType>
    <dei:DocumentPeriodEndDate contextRef="AsOf2026-06-04" id="Fact000010">2026-06-04</dei:DocumentPeriodEndDate>
    <dei:EntityRegistrantName contextRef="AsOf2026-06-04" id="Fact000011">BeyondSpring Inc.</dei:EntityRegistrantName>
    <dei:EntityIncorporationStateCountryCode contextRef="AsOf2026-06-04" id="Fact000012">E9</dei:EntityIncorporationStateCountryCode>
    <dei:EntityFileNumber contextRef="AsOf2026-06-04" id="Fact000013">001-38024</dei:EntityFileNumber>
    <dei:EntityAddressAddressLine1 contextRef="AsOf2026-06-04" id="Fact000014">100                                             Campus Drive, West Side, 4th Floor, Suite 410</dei:EntityAddressAddressLine1>
    <dei:EntityAddressCityOrTown contextRef="AsOf2026-06-04" id="Fact000015">Florham Park</dei:EntityAddressCityOrTown>
    <dei:EntityAddressStateOrProvince contextRef="AsOf2026-06-04" id="Fact000016">NJ</dei:EntityAddressStateOrProvince>
    <dei:EntityAddressPostalZipCode contextRef="AsOf2026-06-04" id="Fact000017">07932</dei:EntityAddressPostalZipCode>
    <dei:CityAreaCode contextRef="AsOf2026-06-04" id="Fact000018">(646)</dei:CityAreaCode>
    <dei:LocalPhoneNumber contextRef="AsOf2026-06-04" id="Fact000019">305-6387</dei:LocalPhoneNumber>
    <dei:WrittenCommunications contextRef="AsOf2026-06-04" id="Fact000020">false</dei:WrittenCommunications>
    <dei:SolicitingMaterial contextRef="AsOf2026-06-04" id="Fact000021">false</dei:SolicitingMaterial>
    <dei:PreCommencementTenderOffer contextRef="AsOf2026-06-04" id="Fact000022">false</dei:PreCommencementTenderOffer>
    <dei:PreCommencementIssuerTenderOffer contextRef="AsOf2026-06-04" id="Fact000023">false</dei:PreCommencementIssuerTenderOffer>
    <dei:Security12bTitle contextRef="AsOf2026-06-04" id="Fact000024">Ordinary Shares, par value $0.0001 per share</dei:Security12bTitle>
    <dei:TradingSymbol contextRef="AsOf2026-06-04" id="Fact000025">BYSI</dei:TradingSymbol>
    <dei:SecurityExchangeName contextRef="AsOf2026-06-04" id="Fact000026">NASDAQ</dei:SecurityExchangeName>
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    <dei:AmendmentDescription contextRef="AsOf2026-06-04" id="ixv-301">This
Amendment No. 1 on Form 8-K/A (this &#x201c;Amendment&#x201d;) amends the Current Report on Form 8-K filed by BeyondSpring Inc. (the &#x201c;Company&#x201d;)
on June 4, 2026 (the &#x201c;Original Form 8-K&#x201d;). The Original Form 8-K reported the appointment of Mr. Min Qiu as Chief Executive
Officer of the Company. At the time of the Original Form 8-K, the Company had not yet finalized the compensatory arrangements for Mr.
Qiu entered into in connection with his appointment as Chief Executive Officer. This Amendment is being filed to disclose those now finalized
arrangements with Mr. Qiu. Except as set forth below, the original filing remains unchanged.</dei:AmendmentDescription>
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