The presence of blood in the semen is called hematosperm. When the amount of blood is high, the semen is red; when the amount of blood is low, it appears as some blood; in some cases, only more red blood cells are found under the microscope. When can hematosperm occur? The causes of hematosperm include: (1) organic causes: stones and prostate stones; infections such as bacterial infections of the urethra, prostate, seminal vesicle and epididymis; tumors such as prostate cancer; traumatic factors such as premature resumption of sexual life after prostatectomy; amyloidosis of the seminal vesicle gland and liver cirrhosis; (2) functional causes: such as excessive masturbation, excessive sexual life or abstinence and excessive interruption of sexual intercourse; (3) sudden onset Hemospermia: may be caused by minor damage to the seminal tract. Mild hematosperm may not affect the quality of semen, while severe hematosperm may affect the physicochemical properties of semen and the movement of sperm, especially infected hematosperm can seriously affect the quality of semen, thus causing infertility. Most of the hematospermia is benign and not seriously harmful, but it often causes tension and anxiety in patients. Anti-infection treatment or appropriate hemostatic agents can be given according to the etiology.