There are many possibilities for green stools, and the more common cases can be divided into the following: 1, gastrointestinal bleeding, if there is stomach bleeding, intestinal bleeding and other diseases, it may cause green or black stools, and the color of the stool is bright. 2, eating too much food containing chlorophyll, such as spinach, rape, and other green vegetables. If too much consumption may cause greenish stools. Especially for patients with indigestion, the symptoms are more obvious. 3, taking drugs containing iron, causing iron to react in the body and eventually lead to green stools. It is recommended to promptly rule out gastrointestinal bleeding and to control as described above. As long as it is not a pathological cause, the greenish stool will gradually disappear as soon as the life is regulated.