Currently, gastric cancer is internationally divided into 4 clinical stages according to TNM staging, i.e. stages I, II, III and IV, and gastric cancer T3N2M0 is clinical stage III. T in TNM represents the size of tumor as well as the degree and depth of invasion of stomach wall, N represents lymph node metastasis, including the size and number of lymph nodes, and M represents whether the tumor has distant metastasis. T3N2M0 of gastric cancer indicates that the tumor is large and invades the dirty peritoneum of the abdominal cavity, with lymph node metastasis, but no distant metastasis, which belongs to the middle and late stage of gastric cancer. For patients with stage III gastric cancer, radical surgery is usually recommended, followed by choosing the next treatment plan according to the pathological results of gastric cancer. Staging of gastric cancer is to better select the treatment plan. Even if patients are in the middle or late stage of gastric cancer, they should actively cooperate with doctors for treatment, and the earlier the treatment, the better the prognosis.