Phimosis refers to the narrow opening of the foreskin, so that the foreskin cannot be turned over to reveal the head of the penis. There are two types of phimosis, congenital and acquired. Congenital prepuce, also known as physiological prepuce, is found in almost every normal newborn and infant. When the child is born, the foreskin mouth is small but the skin is normal and elastic, and the foreskin and the head of the penis are adhered to each other. Generally after 3 to 4 years of age, due to the growth of the penis and the head of the penis, the foreskin can mostly retreat upward by itself, and the foreskin can be turned out to reveal the head of the penis. Some children’s foreskin mouth is very small, so that the foreskin can not retreat, and sometimes the foreskin mouth is as small as a pinhole, so that urination difficulties occur, and even secondary vesicoureteral reflux. Children with prepuce, due to the accumulation of secretions under the foreskin, often irritate the mucous membrane, can cause the head of the penis foreskin inflammation. Acquired prepuce, also known as pathological prepuce, is mostly secondary to penile head prepuce and injury to the foreskin and penile head. The incidence is about 0.8% to l.5%. Acute penile head circumcision, repeated infections, the foreskin mouth gradually scarring and loss of elasticity, the foreskin mouth scarring contracture formation, loss of skin elasticity and expansion ability, foreskin can not retreat upward, and often accompanied by urethral stenosis. This kind of prepuce will not heal on its own. Clinical symptoms] Those with narrow foreskin opening have difficulty in urination, thin urine line, and foreskin puffing up when urinating. Long-term difficulty in urination can cause complications such as prolapse, and even vesicoureteral reflux and hydronephrosis. Urine retention in the foreskin sac often stimulates the foreskin and penile head, prompting it to produce secretions and epidermal shedding, forming excessive foreskin scale. In serious cases, it can cause ulcers or stones to form on the foreskin and head of the penis. The accumulated foreskin scale is milky tofu-like, discharged from the tiny foreskin mouth. Some of the foreskin scale is as big as a soybean, and it accumulates at the coronal groove of the penis head, and a small white lump is visible through the foreskin, which is often mistaken for a tumor by parents and is seen. As the foreskin scale accumulates under the foreskin, it can induce foreskin inflammation of the head of the penis. In acute inflammation, the head of the penis and foreskin are moist and red, and a purulent discharge can be produced. The skin elasticity of the foreskin opening and the presence of scarring should be noted during the examination to distinguish between physiological and pathological prepuce. Treatment】 The foreskin and the head of the penis of newborns are adherent, and there is no need to separate these adhesions. If the parents of the baby boy do not request neonatal circumcision, it is not necessary to examine the head of the penis. The head of the penis is usually separated at 4 years of age, but in some cases later. If there is no priapism or urinary tract infection, there is no need to turn the foreskin and it can be separated on its own. In children who do have inflammation or infection of the foreskin or head of the penis, the inner foreskin plate can be separated from the head of the penis adhesions. In addition, successful topical corticosteroid replacement circumcision has been reported. For those who have symptoms, the foreskin can also be repeatedly tried to be turned up first in order to enlarge the foreskin opening. The technique should be gentle and not overly eager to retract the foreskin up. When the head of the penis is exposed, the foreskin should be restored, otherwise it will cause imbedded prepuce. Most children treated by this method can be cured with age, only a few need to do circumcision. Some people believe that circumcision can reduce the incidence of penile cancer and cervical cancer. However, there is information that there is no significant difference in the incidence of these two cancers between Israel, where circumcision is routinely performed, and the Nordic countries, where circumcision is not widely practiced and where the standard of living is high. It has been suggested that circumcision reduces STD transmission, but there is a lack of substantial clinical data to support this. Circumcision has the advantage of reducing urinary tract infections, especially foreskin infection and priapism, but it is, after all, a surgical procedure and there is still debate about the benefits of the procedure compared to the surgical risks it entails. In the United States, where neonatal circumcision was very popular in the 1960s, it dropped from 90 percent to 64 percent in the 1990s. And there is a downward trend. Circumcision is rarely combined with epispadias or hypospadias, and circumcision should not be performed if epispadias or hypospadias are present. The current consensus indications for circumcision are: ① fibrous narrow ring at the foreskin opening; ② recurrent episodes of penile head circumcision. These two are absolute indications. For those who have narrow foreskin opening after 5 years of age, the foreskin cannot retract to reveal the head of the penis. For children with penile head prepuce, the inflammation is controlled during the acute phase, and the area is soaked several times a day with warm water or 4% boric acid water. After the inflammation subsides, first try to separate the foreskin manually, local cleaning treatment, and consider circumcision when it is not effective. When the operation is done, pay attention to check whether the urethral orifice is narrowed or not, and decide whether to do urethral dilatation or external urethrotomy at the same time. Postoperative appearance of circumcision anastomosis in our department