The invention provides a production method of polyimide pure spinning staple fiber yarn. The method is to process the polyimide fiber with the average length of 39 mm, average fineness of 1.7 dtex and average weight of 33.2 mg through cotton spinning processing to obtain the polyimide pure spinning staple fiber yarn. The method comprises the steps of S1, using an FA201 type carding machine for the processing to obtain 4.28 ktex polyimide staple card silvers, S2, making the polyimide staple card silvers pass through a JWF1310 draw frame for processing to obtain polyimide staple draw silvers with the fixed quantity of 19.5 g per 5m, S3, making the polyimide staple draw silvers pass through an FA458 coarse spinner for processing to obtain polyimide staple roves with the twist of 32.648 twist per meter and the fixed quantity of 3.5 g per 10 m, and S4, making the polyimide staple roves pass through an EJ128K spinning frame for processing to obtain polyimide staple spun yarn with the fixed quantity of 2.9-58 g per 1000 m. According to the cotton spinning process, the production of the pure spinning staple fiber yarn of the fiber is achieved, and the yarn basis is provided for the use and popularization of the fiber in the fields of civil clothes.