Spitting up white water in infants may be related to physiological factors, or it may be caused by milk protein allergy, gastrointestinal tract infection and other reasons. 1. Physiological factors: Since the stomach of infants presents a horizontal position and the cardia sphincter is more relaxed, it is easy to cause reflux, and it may show the situation of spitting up white water. This is a normal physiological phenomenon and does not require special intervention. 2. Milk protein allergy: some infants have milk protein allergy, if the symptoms are mild, they may vomit white water, and may be accompanied by localized rash, abdominal pain and other symptoms. 3. Gastrointestinal tract infection: because the infant’s gastrointestinal tract is infected by bacteria, viruses and other pathogens, under the stimulating effect of pathogenic bacteria, which can easily lead to frequent vomiting, may appear to vomit white water, may also be accompanied by abdominal distension, diarrhea and other manifestations. Infants vomiting white water, there may also be other reasons, it is recommended to go to the hospital in time, complete the examination to determine the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.