The diagnostic criteria for diabetes in children are the same as those for adults. Compared with adult type 2 diabetes, type 2 diabetes in children is significantly different in terms of pathology, physiological characteristics, and the development of the disease, specifically: 1. Obese children are extremely susceptible to diabetes mellitus. Most children with diabetes mellitus have an abrupt onset, with sudden manifestations of polyuria, polydipsia, polyphagia and weight loss. This is referred to as “three more and one less”. School-age children can drink and urinate 3 to 4 liters or more per day, and often drink at night when they are thirsty. The appetite increases but the weight decreases. In young children, urine loss and wasting are often brought to the attention of parents. In infants and young children, the disease is often characterized by the symptoms of enuresis, and polyuria is easily overlooked, and some do not come to the clinic until ketoacidosis occurs. Diabetes in children has a great impact on the large blood vessels and nerves, because the immunity of children is poorer. Therefore, it is more harmful to the body. Physical health can be greatly reduced, and in serious cases it can lead to disability or even loss of life. There is also a certain impact on the development of the body. For example, short stature and delayed development. Diabetes not only affects the child physically, but also psychologically. Also, they are prone to various infections, especially respiratory and skin infections. Children with unsatisfactory long-term blood sugar control may develop cataracts within 1 to 2 years. Retinopathy and renal impairment are caused by microangiopathy in late stage children. Diabetes in children can be treated gradually starting with weight reduction.