The incidence of gastric cancer has been relatively high in the world and in China in recent years, and the diagnosis of gastric cancer is mainly based on the following aspects: 1. clinical manifestations, patients with gastric cancer often have poor appetite, gastrointestinal symptoms, such as abdominal distension, burping, erratic manifestations, and even black stool, which are clinical manifestations. 2. the gold standard for diagnosing gastric cancer is gastroscopy. If the ulcer inside is huge and irregular, local biopsy can be performed to take some tissue for pathological section. If the pathological section confirms the diagnosis of gastric cancer, the patient can be treated as gastric cancer. While confirming the diagnosis, a systemic assessment should be conducted, such as the size of the gastric cancer, the status of regional lymph nodes and the systemic condition. In such cases, preoperative chemotherapy and other comprehensive treatments are needed to transform the cancer into a resectable one before surgery. In case of early gastric cancer, submucosal and intramucosal resection can be performed under gastroscopy; in case of intermediate and advanced gastric cancer, a major gastric resection can be performed under open surgery, which is called regional lymph node dissection; in case of intermediate and advanced gastric cancer, the patient’s physical condition can be good enough to undergo laparoscopic radical gastric cancer resection, including distal gastric, proximal gastric and whole gastric resection plus regional lymph node dissection to achieve the purpose of treatment.