The penis is the external genital organ of the male, and the male urethra is also located in the penis, so the penis has an important role. The scrotum is a skin sac located behind the penis, thin and soft, with a compartment in the center dividing the scrotum into two chambers, each containing testicles, epididymis and vas deferens. Due to the scrotum skin folds, delicate skin, not easy to wash, especially the poor bathing conditions of the workers, often due to the bath scrotum parts of the water is not enough, resulting in soap and alkali residue, irritation caused by inflammation, itching, and then scratching the skin leading to infection, so that the scrotum skin edema and pain. Causes: 1, the patient exists circumcision, phimosis phenomenon: phimosis, phimosis of the penis head is usually always wrapped in the foreskin, must be turned up to reveal the hand; phimosis even with the help of the hand can not make the foreskin turned up to reveal the head of the penis. In this case, the foreskin is more likely to accumulate foreskin scale, and it is difficult to remove, easy to cause the penis and scrotum edema. If you suffer from phimosis or circumcision, you should go to the hospital for circumcision at the right time. 2, masturbation lead to foreskin injury: young people are usually sexually active, often have masturbation phenomenon. Sometimes the masturbation action is too rough, will cause different degrees of foreskin damage. Due to the high degree of mental excitement during masturbation, the damage is relatively small, may not notice, but the wound on the foreskin is very susceptible to bacterial contamination, thus inducing the foreskin glans dermatitis, resulting in penile and scrotal edema. 3, germs infection caused by the penis and scrotum edema: if male friends infected with staphylococcus, streptococcus, Escherichia coli, Candida albicans, trichomonas, chlamydia, mycoplasma, fungi, linbing diphtheria, or other bacteria can cause penile and scrotal edema. 4, do not pay attention to external genital hygiene: young men’s foreskin sebaceous gland secretion is often more vigorous, if you do not pay attention to frequent cleaning of the external genitalia, or cleaning the foreskin is not upturned, the foreskin sebaceous gland secretion will be accumulated in the foreskin, the formation of tofu dregs like foreskin scale. Circumcision is a good cultivator of bacteria, and if not removed in time, it is easy to induce penile and scrotal edema.