Bleeding from ejaculation without pain may be related to acute seminal vesiculitis, seminal vesicle stones and seminal vesicle cancer. 1. Acute seminal vesiculitis: the infection of pathogens as well as local susceptibility factors induce acute seminal vesicles, leading to the infection of seminal vesicle mucosa, edema, erosion, and even bleeding from mucosal injury. 2. Seminal vesicle stone: chronic inflammation of seminal vesicle, lack of certain protease in semen and metabolic disorder are the causes of stone, which can cause laceration of seminal vesicle mucous membrane, hemorrhage of seminal vesicle damage, and the phenomenon of semen with blood during ejaculation. 3. Seminal vesicle cancer: rare in clinic. When the patient suffers from seminal vesicle cancer, the cancer cells erode the blood vessels of seminal vesicles, causing the blood vessels on the surface of seminal vesicles to rupture and bleed, the ejaculate will have semen with blood without pain symptoms. When bleeding ejaculate without pain occurs, the patient should consult doctor in time, follow the doctor’s instruction for further examination, clarify the cause with the help of doctor, and carry out targeted treatment or therapy.