Gastric cancer is the most common malignant tumor worldwide and in China. The exact cause is not clear and is related to geographical environment and dietary and lifestyle factors, Helicobacter pylori infection, precancerous lesions, genetics and genes. Gastric cancer has no specific symptoms or even no symptoms in the early stage. As the tumor progresses and affects the function of stomach, more obvious symptoms will appear, but the symptoms are not typical. The common symptoms include stomach pain, nausea, vomiting, bleeding and black stool, etc. Surgery is the main treatment for gastric cancer and the only way to cure it. It includes radical resection and palliative surgery. In addition, chemotherapy is also an important treatment method for gastric cancer treatment. The prognosis of gastric cancer is closely related to the early or late stage of the disease and whether the treatment is appropriate. Gastroduodenal ulcer is a limited round or oval mucosal defect called gastroduodenal ulcer. Its development is influenced by several factors, the most important of which are abnormal gastric acid secretion, H. pylori infection and disruption of mucosal defense mechanisms. The vast majority of gastroduodenal ulcers can be controlled and the ulcer can heal with medical treatment. Surgical treatment is mainly used for patients with complications of gastroduodenal ulcers such as acute perforation, scarring stenosis pyloric obstruction, acute hemorrhage or ulcer patients for whom drug therapy is ineffective, and malignant changes of gastric ulcers. Commonly used procedures include major gastrectomy and vagotomy. Major gastrectomy not only reduces gastric acid and pepsin secretion, but also removes the ulcer itself as well as the site of the ulcer’s predilection. Gastric vagotomy reduces acid secretion by blocking the vagus nerve.