1, seminal vesiculitis: seminal vesiculitis is the most common cause of hematospermia. The sperm vesicle wall segment is 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 strong contraction of the seminal vesicles makes the capillaries rupture causing bleeding, which is characterized by hematospermia throughout. 2, prostatitis: prostate fluid is the main component of semen, accounting for about 30% of semen, when the prostate is inflamed, can also appear hemorrhagic semen. The last ejaculation of the semen is characterized by blood-colored semen. 3, seminal frenulum: chronic seminal frenulum infection can easily lead to hypertrophy of the seminal testis, causing urinary difficulties and painful ejaculation. 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. 4, prostate hyperplasia: prostate hyperplasia when the surface of the blood vessels anger, these small veins migrate expansion, sexual intercourse semen when the posterior urethra strongly contracted, so that the small veins rupture, resulting in hematosperm. 5, seminal vesicle or prostate tumor. 6, blood disease: patients with blood disease because of the tendency to bleed, can also appear hematosperm. 7, urethral injury: frequent sexual intercourse makes the prostate gland, the seminal vesicles overly congested, which can also cause hematospermia. Especially when the urethral mucosa is damaged due to too intense sexual intercourse or improper sexual position, semen with blood can appear. The severity 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 injury, not only is the semen bright red, but also the phenomenon of blood dripping from the urethra after ejaculation occurs.