Sweating during sleep can be caused by high temperature, upper respiratory tract infections, hypocalcemia and other reasons. 1. Excessive temperature: if the temperature of the room is too high during the baby’s sleep, lack of air circulation, dry air and lack of water, bedding and clothing is too thick, etc., it will lead to the baby through a lot of sweating to dissipate heat, which is caused by physiological factors, without special treatment. 2. Upper respiratory tract infections: viruses invade the mucous membranes of the upper respiratory tract of the baby, inducing the hypothalamus thermoregulation point to rise, which in turn causes the body temperature to rise, so the baby will increase sweating to dissipate heat. In addition, suffering from pneumonia, acute tonsillitis and other infectious diseases will also sleep sweating. 3. Hypocalcemia: long-term malnutrition, lack of light and other factors leading to a lack of vitamin D and calcium intake, the baby’s nervous system excitability increases, easy to sleep during the irritability, muscle contraction and twitching and other symptoms, so it will be sleep sweating. Baby sleep sweating may be related to a variety of factors, serious cases are recommended to seek medical attention to clarify the diagnosis.