A case of arterial priapism was treated by superselective transcatheteric autologous clot embolization of cavernosal artery 25 days after blunt periheal trauma. No immediate improvement was noted but the priapism subsided on 48th day after the procedure. Normal physiclogic erectlie function was achieved on 53rd day after the procedure, and the period of postprocedure impotence was shortened, as compared with previously reported cases. Autologous blood clot embolization may be an effective treatment method even in delayed priapism, and superselective technique is thought to be more effective to shorten the postprocedure erectlie dysfunction.