Baby’s screaming at night may be caused by environmental factors, dietary reasons, calcium deficiency and other reasons. 1. Environmental factors: if the baby sleeps in an environment that is too bright, too hot or too cold, or suddenly there are loud noises, it may cause the baby to sleep at night screaming. 2. Dietary reasons: if the baby did not eat enough before bedtime, during sleep may appear hungry, thus appearing night sleep screaming; if the baby ate too much before bedtime, may lead to the baby’s accumulation of food, abdominal distension and other uncomfortable symptoms, the baby may also appear night sleep screaming. 3. Calcium deficiency: if the baby in the feeding period, always stay at home, do not go out in the sun, or not timely calcium supplement, etc., may lead to the emergence of rickets, thus the emergence of night sleep screaming. Baby sleep screaming at night may also be caused by other reasons, it is recommended to go to the hospital in time to improve the examination to clarify the cause of the disease, give targeted treatment or standardized treatment.