The main consideration of black poop is blood in the stool, and both physiologic and pathologic factors are generally considered. 1. Physiological factors: when the patient eats blood products such as sheep blood, duck blood, etc. or spinach, it will lead to a large amount of blood products and folliculin in the food, resulting in black poop. 2. Pathological factors: when the patient suffers from peptic ulcer, cirrhosis of the liver, acute erosive hemorrhagic gastritis, digestive tract tumors, due to upper gastrointestinal bleeding, there will also be a black poop, it is recommended to improve the gastroscopy as soon as possible, upper gastrointestinal imaging, to clarify the cause of bleeding for appropriate treatment. In addition, there may be other reasons for black poop, it is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease, and then give targeted treatment or therapy under the guidance of the doctor.