Children who suddenly wake up crying at night may be caused by physiological factors, may also be caused by vitamin D deficiency and other pathologic factors, can take general treatment and vitamin D supplementation and other medications. 1. Physiological factors: children may be excited before bedtime, have nightmares at night, or be infected by environmental factors such as thunder, all of which may lead to sudden waking up at night and crying. Parents to more soothing, not too excited before bedtime, to create a quiet and comfortable atmosphere for the baby to sleep, to give the baby enough sense of security. 2. Vitamin D deficiency: Children with vitamin D deficiency are prone to night terrors and excessive sweating. There will also be the phenomenon of suddenly waking up at night and crying, need to take oral vitamin D treatment under the guidance of the doctor. Children suddenly wake up crying at night, there may also be other reasons, such as colic, indigestion, fever, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, and then give targeted treatment. All of the above medications should be used after evaluation by a doctor.