The most common cause of pain in the upper abdomen after a meal is ulcer disease, also known as gastric ulcer. Its typical manifestation is postprandial pain, which occurs for reasons related to Helicobacter pylori infection. Gastroscopy can also reveal congestion, edema and even erosion of the mucosa of the gastric wall, so attention should be paid to diet and appropriate medication to protect the gastrointestinal mucosa. In addition, some patients are affected by malignant tumors in the stomach, which are more common in middle-aged and elderly patients. The factors of occurrence are influenced by personal factors, dietary structure and family genetic factors, and gastroscopy can confirm the diagnosis.