When a baby has green stools, several aspects are usually considered: the first and most important aspect to exclude is to see if the milk intake is not enough. When the milk intake is insufficient, there is not a lot of food in the intestine, and the bile in the intestine, which is not fully utilized and broken down, will be excreted in its original form, and then the stool will tend to be green. Therefore, the adequacy in feeding needs to be focused on. The second point, formula-fed babies, stools can also appear green, which is related to the production process of milk powder, iron contained in this case of green stools, no special treatment, including the need for deliberate replacement of milk powder. The third point is that when the baby has a cold, such as the stomach, feet, lower limbs are not well warm, intestinal peristalsis increases, the stool is also easy to be green. When there is green stool, the baby has no special abnormalities, so observation is the main focus. If there are any accompanying symptoms, you need to analyze what the possible causes are in conjunction with the specific symptoms. When convenient, a preliminary stool routine can be checked to make a preliminary differential diagnosis and rule out special problems such as enteritis. Parents who have persistent and repeated green stools are more worried and need to ask the doctor to make a more specific judgment.