As society progresses and material culture improves, more and more mothers and fathers are joining the workforce after childbirth, so more and more babies are eating milk powder. When babies who eat milk powder have frequent skin manifestations and digestive symptoms, we should be highly alert to whether the baby is allergic to milk protein. Skin manifestations are mainly eczema, the child’s face, trunk and limbs can appear erythematous papules, in serious cases can appear oozing, accompanied by varying degrees of itching, because the child is small, there is no way to express in words so often manifested as crying and restless. For small infants, they always have crying and diarrhea after eating milk, accompanied by a lack of weight gain and poor nutritional status. In some cases, children with simple bloody stools that have not been relieved by conventional treatment should also be considered allergic to milk proteins. If the bloody stool disappears quickly after switching to amino acid formula, then the child can be clearly diagnosed as having bloody stool due to milk protein allergy. Therefore, when the above symptoms occur in a baby who eats milk powder, the mother should think about whether it is a manifestation of milk protein allergy and seek medical attention in time to change the milk powder for the child to ensure the normal growth and development of the child.