Baby sleep suddenly vomit is usually due to too much food before bedtime and other physiological factors, as well as indigestion, acute enteritis and other pathological factors. 1. Physiological factors: if the baby ate too much food before bedtime or ate too fast coupled with the problem of sleeping position, may appear to sleep suddenly vomit. 2. Pathological factors: due to improper diet and other conditions caused by indigestion may also make the baby sleep suddenly vomit the situation; due to infection caused by acute enteritis may also lead to the baby sleep suddenly vomit, usually accompanied by diarrhea, fever and other symptoms. Baby sleep suddenly vomit, there may be other reasons, it is recommended to go to the hospital in time to improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.