The diagnosis and treatment specification of gastric cancer can be analyzed from the following points: 1. definition of gastric cancer, high-risk factors, etc.; 2. clinical manifestations, the common ones include upper abdominal discomfort, loss of appetite, weakness, weight loss, nausea, vomiting, vomiting blood, black stool, etc., which vary from person to person; signs, no obvious signs in early stage, abdominal mass can be seen in late stage, when there is gastrointestinal bleeding or perforation, corresponding clinical signs can also appear 3, auxiliary examinations, gastroscopy, CT, MRI, pathological diagnosis, the diagnosis and treatment specifications have analyzed and staged the auxiliary examinations in each period; 4, differential diagnosis, differentiate from benign lesions of the stomach, other malignant neoplastic diseases of the stomach; 5, treatment, different stages of tumors, different general conditions of patients, treatment plans are also different, specific need to be combined with the actual situation of patients to develop In addition to active treatment, patients with gastric cancer should undergo regular review to prevent and treat complications. Therefore, it is important to pay attention to the diagnosis of gastric cancer and choose the treatment plan with the actual situation of the patient.