PURPOSE: To provide the polysulfone resin hollow yarn membrane for medical purposes which is a hollow yarn membrane having less adhesion of blood proteins, platelets, etc., on the membrane surfaces and to be less changed in filtration rate with the lapse of time and has excellent safety.

CONSTITUTION: This polysulfone hollow yarn membrane for medical purposes is the hollow yarn membrane composed of polysulfone and polyvinyl pyrrolidone and has 20 to 50% presence ratio of the polysulfone on particulrly the inside surface of the hollow yarn membrane with which blood comes into contact directly.