Anorexia nervosa is a condition in which a child has a prolonged period of loss or loss of appetite, or even refusal to eat, in addition to other acute and chronic illnesses. It can occur in children of all ages, especially in children aged 1-6 years, but is significantly less common in school-age children, with a higher incidence in urban areas. If the child’s nutritional development is relatively good and only occasionally has a low appetite, it cannot be considered as anorexia nervosa. The disease starts slowly and has a long course. Children with long-term anorexia may suffer from malnutrition, physical weakness, decreased resistance to disease, and even affect growth and mental retardation. In the past, anorexia was not considered an independent disease, but a symptom that occurred in the course of other diseases. In recent years, with the gradual improvement of the understanding of the disease and the update of diagnostic techniques, the incidence of the disease seems to be increasing year by year, especially in urban children, and now it has become one of the more common diseases in pediatrics. Anorexia nervosa is characterized by clinical complaints of anorexia. The appetite is reduced, or no appetite, the amount of food is reduced, the stool is dry or thin, the general spirit is still possible, the disease for a long time see refusal to eat, the face is yellow, the body is thin, fatigue and other symptoms. Generally, there is no change in heart rate, blood pressure and pulse, and there are no obvious abnormalities in growth and development; some have decreased or no weight gain or slow growth, dry skin, thin yellow hair, dryness or stunting.