Drinking black coffee generally will not discharge black stools, may be related to gastric ulcer, gastrointestinal bleeding, benign tumors, etc., may also be caused by physiological reasons, it is recommended to consult a doctor to clarify the cause of the disease. 1. Physiological reasons: in general, drinking black coffee will not discharge black stool, but if you take blood iron, activated charcoal, etc., or eat black sesame, mulberry, etc. may be discharged black stool, is normal. 2. Gastric ulcer: if the gastric ulcer is not treated in time, resulting in bleeding of the ulcer in the stomach, black stools can occur, which is a more serious situation, and you should consult a doctor in time to find out the cause of the disease. 3. Benign tumors: the surface of benign tumors such as intestinal polyps and gastric polyps can be broken and ruptured, and blood vessels can bleed, which may lead to the discharge of black stools. Drinking black coffee generally will not discharge black stools, excluding physiological reasons, if there are the above factors, should consult a doctor in time to clarify the diagnosis.