Two-year-old baby intestinal micro-ecosystem establishment has been relatively sound, intestinal digestion, absorption function are still good, will not always repeated diarrhea. If always diarrhea to consider the following situations: First, focus on whether the diet structure is unreasonable, always diarrhea may be eating too full, eat too much, especially greasy, stimulating food to eat too much, not easy to digest, always repeated diarrhea. Second, pay attention to whether the baby has food allergies and other factors, such as allergies to eggs, milk or certain other foods. If the diet often intake of such easily allergic food, it will lead to recurrent diarrhea, in daily life to pay attention to avoid. Third, pay attention to whether the baby has chronic enteritis, or inflammatory bowel disease and other gastrointestinal tract underlying diseases. Babies with this type of underlying disease are always prone to diarrhea and should go to a pediatric gastroenterology clinic for consultation, examination and treatment.