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Note 1 - Nature of the Business - Schedule of Subsidiaries (Details) | Mar. 31, 2025 | Jan. 31, 2025
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BeyondSpring Pharmaceuticals Inc. [Member] |  |
Ownership Percentage in Subsidiaries | 100.00% |
BeyondSpring Ltd. [Member] |  |
Ownership Percentage in Subsidiaries | 100.00% |
BeyondSpring HK [Member] |  |
Ownership Percentage in Subsidiaries | 100.00% |
Wanchun Biotechnology Limited [Member] |  |
Ownership Percentage in Subsidiaries | 100.00% |
Wanchun Biotechnology (Dalian) Ltd. [Member] |  |
Ownership Percentage in Subsidiaries | 100.00% |
Dalian Wanchunbulin Pharmaceuticals Ltd. (“Wanchunbulin”) [Member] |  |
Ownership Percentage in Subsidiaries | 57.97% |
Beijing Wanchun Pharmaceutical Technology Ltd. [Member] |  |
Ownership Percentage in Subsidiaries | 57.97% |
SEED Therapeutics Inc. [Member] |  |
Ownership Percentage in Subsidiaries | 37.56% | 14.37%
SEED Technology Limited [Member] |  |
Ownership Percentage in Subsidiaries | 57.97% |
SEED Therapeutics US, Inc. [Member] |  |
Ownership Percentage in Subsidiaries | 37.56% |
Wanchun Hongji (Dalian) Pharmaceuticals Ltd. [Member] |  |
Ownership Percentage in Subsidiaries | 37.56% |

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