After a man has sex, he usually only needs warm water to clean his penis. After sexual intercourse, the mucus secreted from the vagina or the semen ejaculated will stick to the external genitalia, especially the perineum and scrotum area, which, if not cleaned up for a long period of time, may harbor a large number of bacteria and viruses, which may lead to a series of diseases. Specific cleaning process is, if the foreskin is too long should be turned to the coronal groove, the foreskin scale will be removed together, if it is the circumcision or the foreskin is long and difficult to turn up the person, should do circumcision, in the process of cleaning, try to avoid the use of skin care products, etc., because of the irritation of the larger, directly with warm water can be cleaned. If there are uncomfortable symptoms, it is recommended to go to the regular hospital in time for diagnosis and treatment.