Causes four months baby always sweat at the back of the head, mainly including the following situations: first, due to physiological reasons, due to four months baby age is relatively small, the metabolic rate is relatively fast, the baby’s heartbeat as well as the number of breaths is significantly faster than adults, will cause the baby to sweat a lot of cases. The baby due to the age is relatively small, the development of plant nervous function is not perfect, the control of sweat glands is relatively poor, which is also caused by physiological sweating. Secondly, due to pathological factors, if the baby has vitamin D deficiency rickets and other pathological causes, it will cause the back of the head sweating more, the whole body sweating is also more, accompanied by occipital baldness, chicken chest, rib beads and other symptoms.