Bedwetting is often seen in enuresis. It is defined as involuntary urination that occurs after sleep at age 5 years or older, usually at a frequency of >1-3 times per month. The disease is most common in boys. 6-7 year olds have the highest incidence of the disease. Enuresis can be categorized as primary and secondary, simple and complex. Those who have enuresis since childhood and persist, and there is no obvious organic lesion of the urinary tract or nervous system. It is called primary enuresis, accounting for 70% to 80%. Secondary to lower urinary tract obstruction, cystitis, neurogenic bladder distension and other diseases is called secondary enuresis manifestations, in addition to enuresis, daytime urinary frequency, urinary urgency, urinary difficulty, urinary stream fine and other symptoms. Simplicity refers to only combined night bedwetting, daytime asymptomatic, not accompanied by anatomical or functional abnormalities of the urinary system and the nervous system; complexity refers to the bedwetting at night in addition to the daytime accompanied by symptoms of the lower urinary system, often secondary to urinary or neurological disorders in children most, the most common is still the primary simple enuresis. The main causes of primary enuresis are as follows: 1, delayed cortical development and cooperation, can not inhibit the cremasteric center of urination, after sleep, the forced urinary muscles appear uninhibited contraction of urine discharge; 2, too deep sleep: these children sleep very deeply at night, it is not easy to wake up, wake up, go to the residence is still half-awake. Can not accept from the bladder dirty urine and wake up to occur reflex urination; 3, psychological factors: the prevalence of mental illness in children with this disease is higher than normal children. And enuresis often begins or worsens after mental stimulation. 4, genetic factors: both parents or school parties have a history of enuresis. And monozygotic twins at the same time the occurrence of enuresis is more than dizygotic twins. Secondary enuresis is often seen in organic diseases. Such as urinary tract infection, uremia, collar and whisker seizures, intellectual developmental disorders, neurological lesions. Some of them are caused by local stimulation of genitourinary organs, such as prepuce, phimosis, vulvitis, congenital urethral malformation, urinary tract infection, followed by systemic diseases such as crural cleft and diabetes mellitus. It is mostly seen in adults. However, the vast majority of children’s enuresis has nothing to do with disease, and is caused by psychological factors or various other factors.