The actual liquid is often considered to be a normal physiological phenomenon when the penis is erected, and it may be related to pathological factors such as prostatitis and urethritis. 1. physiological factors: male penis erection, sexual excitement can be caused by accessory sex gland secretion is relatively active, penis, prostate and urethra are in a state of congestion, prostate fluid and other gonadal secretion of the liquid may be seeped out in advance, through the urethra discharged, the liquid is usually colorless and tasteless, and is not accompanied by pain and other symptoms of discomfort, belong to the normal physiological phenomenon. 2. Pathological factors: (1) prostatitis: the prostate can appear congestion, edema, increased secretion, end of urination or erection can cause the liquid from the urethral orifice, mostly accompanied by odor, and can appear urinary pain, urinary urgency and other symptoms. (2) Urethritis: mostly related to bacterial infection, can cause patients to appear frequent urination, urinary urgency and other symptoms, especially the history of unclean sexual intercourse may cause non-gonococcal urethritis, inflammatory stimulation can cause fluid flow from the urethra after erection. After excluding physiological factors, it is recommended that those who have fluid coming out of the penis during erection should consult a doctor in time to improve the urine routine, urine culture and other tests to identify the cause of the disease and then actively treat it, so as not to delay the condition.