Two year old baby sweating while sleeping is generally classified as physiological sweating and pathological sweating. Physiological hyperhidrosis is usually caused by a child’s good growth and development, healthy and no other diseases. The two-year-old baby is in a critical period of growth and development, the body’s metabolism is very vigorous, the hypothalamus thermoregulatory center is more sensitive to stimulation, so a little excitement or stimulation is easy to sweat more. The baby’s body is very metabolic and sensitive to stimuli. If these exogenous changes are made, excessive sweating can be avoided. However, pathological hyperhidrosis cannot be ruled out. Pathological causes are generally classified as nutritional deficiencies or metabolic diseases, such as active rickets, malnutrition, infectious diseases (such as pneumonia, tuberculosis), rheumatic diseases, etc., which can be caused.