Tarry stool is common in gastric ulcer, duodenal ulcer, esophagogastric varices, esophagitis, hemorrhagic gastritis, upper gastrointestinal tract tumors and other diseases. 1. Most of the tarry stools are caused by upper gastrointestinal bleeding, such as gastric ulcer, duodenal ulcer, etc., because the bleeding of ulcer is dominated by black stools, and the amount of bleeding is relatively large, which is accompanied by the symptom of vomiting blood. 2. Diseases such as esophageal varices and cirrhosis of the liver can also cause tarry stools accompanied by vomiting of blood, but most of them are painless. 3. Esophagitis and hemorrhagic gastritis can also cause black stools, which usually have no other symptoms and need to be clearly diagnosed through gastroscopy. 4. If upper gastrointestinal tract tumors, such as stomach tumors, will vomit blood, also accompanied by black stools, if there is no symptom of vomiting blood, black stools is the main symptom. It is recommended that patients go to the regular hospital to do detailed examination, clear diagnosis of the cause of tarry stools, and actively cooperate with the treatment.