A. Seminal vesicle inflammation: seminal vesicle inflammation is the most common cause of hematospermia. The sperm vesicle wall segments are thin, and when the sperm vesicle is inflamed, the sperm vesicle wall becomes edematous, congested, and the capillaries on the sperm vesicle wall become more brittle. When ejaculation, the seminal vesicles strongly contract to make the capillaries rupture causing bleeding, which is characterized by hematospermia throughout. The last ejaculation of the semen is characterized by blood-colored semen. As the seminiferous tissue is congested and edematous, the mucosa is prone to rupture and bleeding. Especially during sexual intercourse, the posterior urethra strongly contracted, more likely to appear hematosperm. Fourth, urinary fatigue inflammation: When the urethra is inflamed, especially the urethral inflammation at the seminal mound, it is easy to appear hematosperm, which is characterized by, the front section of semen with blood. Fifth, posterior urethral varicose veins: there are many small veins in the bladder neck that continue directly to the posterior urethra, these small veins migrate and expand, and when the posterior urethra is strongly contracted during sexual intercourse and sperm discharge, the small veins rupture, causing hematosperm. Sixth, seminal vesicle or prostate tumor. Seven, blood disease: patients with blood disease because of the tendency to bleed, can also appear hematosperm. Eight, urethral injury: frequent sex makes the prostate, the seminal vesicles overly congested, can also cause hematospermia. Especially when the urethral mucosa is damaged due to too intense sexual intercourse or improper sexual position, the semen can appear with blood. The degree of hemorrhage is related to the degree of injury, with blood in the semen in the anterior segment of minor injuries, or microscopic hematuria. In severe injuries, not only is the semen bright red, but also the phenomenon of blood dripping from the urethra.