Long-term dark green stools may be related to dietary factors, or may be caused by indigestion, liver and gallbladder diseases. 1. Dietary factors: If you consume too much green leafy vegetables for a long period of time, because green leafy vegetables contain more chlorophyll, it will cause dark green color in the stool, and not accompanied by any other discomforts, which is a normal physiological phenomenon, no need to worry about it, and no need for special treatment. 2. Indigestion: some people have irregular diet for a long time, often overeating, which will easily lead to frequent indigestion, resulting in more food can not be digested and absorbed quickly, and stay in the intestine for a long time, easy to produce fermentation reaction, which may make the stools dark green for a long time, and may be accompanied by abdominal bloating, abdominal pain and other symptoms. 3. Liver and gallbladder diseases: For example, cholecystitis, cholangitis, cirrhosis and other liver and gallbladder diseases may lead to dark green stools, which may be accompanied by symptoms such as fatigue, loss of appetite and weight loss. Prolonged dark green stools may also be caused by other reasons. If accompanied by obvious discomfort symptoms, you should seek medical advice as soon as possible, and after a clear diagnosis of the cause, be guided by a doctor to carry out the treatment, do not be negligent, so as to avoid delays in the condition.