As the largest accessory gonadal organ in men, the prostate has multiple physiological functions. The prostate gland forms the wall of the proximal urethra, including the internal urethral sphincter, which consists of a ring of smooth muscle fibers surrounding the urethra of the prostate, controlling the discharge of urine from the bladder and helping the semen that has entered the seminal vesicles and the prostate gland to exit the body via the urethra during ejaculation. The prostate gland has an exocrine function and can discharge about 0.5-2.0ml of thin, milky white prostate fluid every day. prostate fluid is an important part of semen, accounting for about 25%-33% of the total semen, and the fructose, amino acids, lecithin and other substances contained in it are the main energy source for sperm activity; the large amount of potassium citrate, phosphate, sodium, potassium and calcium in prostate fluid can alkalize semen to moderate the acidic environment in the female vagina. The prostate fluid secretes a large amount of semen liquefying enzyme to help liquefy the coagulated semen; the prostate fluid contains hyaluronidase to assist the sperm entering the vagina to penetrate the cervical mucus and the ventral membrane of the egg, promoting the union of sperm with the egg. The prostate also has some endocrine function in that it allows for the rapid metabolism of testosterone into more potent androgens that are delivered into the bloodstream. The prostate also regulates hypothalamic and pituitary function to some extent.