Black stools in patients with liver disease are often considered to be caused by gastrointestinal bleeding due to liver disease, but food and drug factors cannot be ruled out. When patients have liver diseases such as cirrhosis and liver cancer, it is easy to trigger portal hypertension and increase the pressure of collateral circulation, which causes esophageal fundus varices, when the condition further deteriorates or after eating raw and hard food, it can cause gastric mucous membrane damage, which results in the rupture of esophageal fundus varices and bleeding, and when the amount of bleeding is small, through the digestive tract of the gastric acid and other digestive components of the blood, the patient can show black stools. Cirrhosis patients who take blood products, bismuth (such as bismuth citrate potassium capsule) may also cause black stools, generally stop this kind of food and drugs after the stools can be restored to normal color. Therefore, patients with liver disease should pay attention to their dietary habits, avoid overeating, smoking and drinking, etc. Meanwhile, they should always pay attention to the color and character of the stool. Liver disease patients with black stools are advised to consult a doctor in time, under the professional guidance of the doctor for diagnosis and treatment.