Gastric ulcers 3cm to 5cm are more serious. Gastric ulcers are ulcers caused by the gastric mucosa being digested by gastric acid/pepsin itself under certain circumstances. It mostly occurs in the corner or sinus of the stomach, and on the side of the lesser curvature of the body of the stomach. The main symptom of gastric ulcer is dyspepsia, which is characterized by postprandial epigastric pain that gradually resolves after 1~2h. Gastric ulcers are generally <2cm in diameter, and ulcers >2cm need to be differentiated from malignant gastric ulcers. The shape of ulcerative gastric cancer under endoscopy is mostly irregular, the bottom is uneven, the moss is dirty, and the edge is nodularly elevated. Endoscopic examination and biopsy can determine whether there is cancer or not. Gastric ulcer 3~5cm should go to the hospital in time for consultation, clear pathologic typing, and treatment under doctor’s guidance.