3 year old baby night sleep sweat, may be sleeping environment temperature is too high, upper respiratory tract infection, indigestion and other reasons. 1. Sleeping environment temperature is too high: the baby sleeps where the temperature is too high, the lack of air circulation, bedding clothing is too thick and other factors lead to increased body surface temperature, coupled with the baby’s thermoregulatory function is not yet perfect, so there will be a large amount of sweating to dissipate heat. 2. Upper respiratory tract infection: viral infection of the upper respiratory tract of the baby caused by local mucosal inflammatory reaction, in addition to inducing the hypothalamus thermoregulation point rises resulting in fever, so there will be a large amount of sweating to dissipate heat. 3. indigestion: baby digestive function is not yet fully developed, eating too much, stomach cold, food dry and hard and other factors lead to indigestion, sleep gastrointestinal flatulence and sweating more. 3-year-old baby sleep at night sweating, there may be other reasons, it is recommended to go to the hospital in time to improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.