The baby sleeps with a lot of sweat on the head may be physiological reasons, caused by children’s physiological structure; may also be pathologic hyperhidrosis, such as infectious diseases. 1. Physiological reasons: the baby’s metabolism is more vigorous than that of adults, and the baby’s active sweat glands are concentrated in the head, so it will cause the head to sweat more when sleeping, which is usually seen within one hour after sleeping. In addition to sleep bedding is too thick will also cause increased sweating. 2. Pathological reasons: if urinary tract infection or respiratory system infection will lead to inflammatory factor secretion to make the body temperature rise, resulting in increased sweating while sleeping. Infection with tuberculosis can also cause increased sweating, mostly in the afternoon. The baby sleeps a lot of head sweat may also have other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.