As children’s health care becomes more popular, more and more parents are hearing the diagnosis of “prepuce or circumcision. More and more children are being seen in pediatric urology clinics for prepuce problems. However, parents are still confused about how and when to treat pediatric prepuce due to a lack of knowledge in this area and the influence of some traditional concepts. Prepuce is a condition in which the foreskin of the male penis cannot be turned up and the head of the penis cannot be exposed due to narrowing of the foreskin opening or adhesion of the foreskin to the head of the penis. There are two types of pediatric prepuce: physiological (congenital) prepuce and pathological (acquired) prepuce. Almost every normal little boy has physiological prepuce after birth, and the prepuce opening of patients with prepuce is very small, and the urine line is extremely thin when urinating, and the prepuce is bulbous and inflated, often causing urine to accumulate in the prepuce sac. The prepuce is a very important part of the body. The accumulated foreskin scale is sometimes milky tofu-like and can be discharged from the tiny foreskin mouth; some foreskin scale is the size of a soybean and accumulates at the coronal groove of the head of the penis, which looks like a small white lump through the foreskin and is often mistaken for a tumor. As the foreskin scale accumulates under the foreskin, it can induce foreskinitis of the penis head. In acute circumcision, the head of the penis and foreskin will be moist and red and swollen, and purulent secretions can be produced, causing difficulty in urination, affecting the growth and development of the penis, and even inducing penile cancer. Pathological prepuce can also be accompanied by urethral stenosis, which cannot be cured by itself and must be treated. So how to treat prepuce? Early concepts suggest conservative treatment by foreskin expansion. The foreskin is manually turned up to reveal the head of the penis, and then the foreskin is cleaned. However, many children have an enlarged foreskin opening that can be turned up to expose the head of the penis, but the foreskin is still long and covers the entire head of the penis, a condition called phimosis. There are still hazards such as unhygienic and abnormal irritation in circumcised pediatric patients, so we do not recommend putting children through the pain of foreskin expansion without solving the underlying problem. The most straightforward, effective and thorough is circumcision. So, when is a good time for pediatric circumcision patients to have surgery? Generally speaking, the inner plate of the foreskin in children with prepuce is often infiltrated with inflammatory cells in the superficial dermis at the age of 3 to 15 years old, reaching the full layer at the age of 15 to 20 years old; this change becomes more and more obvious as age increases. Thus, in order to effectively treat circumcision, especially to prevent the occurrence of penile cancer, circumcision should be performed as early as possible, before pathological changes occur. And those who have the following conditions should be operated as early as possible: ① foreskin with fibrous stenosis ring; ② recurrent episodes of penile head circumcision; ③ serious narrowing of foreskin opening after school age (6~7 years old).