Gastric cancer has a high incidence rate in China, with men significantly higher than women, and the peak age of incidence is 45-60 years old, but the incidence has tended to be younger in the last decade. The etiology of gastric cancer is very complicated, and it is related to dietary habits, smoking, genetic factors, lack of gastric acid, etc. If you suffer from gastric ulcer (malignant rate is about 5%), chronic atrophic gastritis (malignant rate is about 10%), gastrointestinal epithelial hyperplasia, gastric polyposis, etc., you should pay high attention to them. When there is: irregular upper abdominal discomfort, pain; unexplained loss of appetite, weakness, weight loss; nausea and vomiting, swallowing difficulties; vomiting blood, black stool, etc. should promptly seek medical attention for standardized examination. X-ray gas-barium double examination: The accuracy rate of examination can reach more than 80%. Fiberoptic endoscopy: It is the most direct, accurate and effective method to diagnose gastric cancer. The lesion can be clearly seen under the microscope, and tissue biopsy can be taken for pathological examination and diagnosis. Treatment: Surgery includes: 1. radical resection 2. palliative resection 3. short-circuit surgery, chemotherapy includes preoperative and postoperative systemic chemotherapy and intraperitoneal chemotherapy. Radiotherapy includes preoperative radiotherapy: to shrink the mass and improve the surgical resection rate; intraoperative radiotherapy: to irradiate the lymph nodes and subclinical lesions that are not completely removed; postoperative radiotherapy. In addition, biological targeting therapy, tumor immunotherapy, selective arterial cannulation chemotherapy and heat therapy are also available. The key to the treatment of gastric cancer is early detection, early treatment, cooperation between doctors and patients, and establishing confidence to overcome the disease in order to achieve satisfactory results.