The cure rate of early gastric cancer can reach 95-100%, so it becomes very important to detect and diagnose early gastric cancer. The reason for better treatment effect of gastric cancer in Japan is related to the high detection rate of early gastric cancer. Like most malignant tumors, gastric cancer has a long detectable clinical period, but it is often not detected early due to its deep location, which is easily ignored by patients and clinicians, and the lack of sensitivity and specificity of screening methods. At present, it is not possible for us to have free gastroscopy screening for all people as in Japan, so it is possible to detect more early gastric cancer by increasing the screening rate for high-risk groups through doctors. As ordinary patients, they also need to know about this: i. Pay attention to the awareness of risk factors, especially the importance of family history. People with family history of gastric cancer or other gastrointestinal malignancies may have genetic susceptibility and should pay attention to regular checkups. Quit risk factors such as bad dietary habits, smoking and alcohol abuse. Second, regular screening of the population should be strengthened. It is better to enter the electronic gastroscopy, while the electronic gastroscopy can visually observe the morphology and condition of the gastric mucosa and detect gastric mucosal lesions early. But the population census requires a lot of manpower and material resources, most areas in China do not yet have the conditions required for census. Regular gastroscopy for high-risk groups. For the high-risk patients with precancerous lesions of gastric cancer suggested by previous gastroscopy, regular gastroscopy is the most important means: common precancerous lesions include 1) chronic atrophic gastritis; 2) chronic gastric ulcer; 3) gastric polyp; 4) partial gastrectomy; 5) other precancerous lesions such as giant gastric mucosal hypertrophy and warty gastritis, etc. Pay attention to the symptoms of “gastritis”. For those patients who have mild “stomach pain” and “abdominal discomfort”, they should not be considered as “gastritis” only, and outpatient doctors should listen carefully to patients’ descriptions and do corresponding examinations. Doctors should listen carefully to the patient’s story and perform the appropriate tests. They should not just make a hasty diagnosis of “chronic gastritis”, but should perform gastroscopy on these high-risk groups, and doctors should be especially vigilant. With the development of molecular biology, more and more molecular markers and high-tech tumor micro-diagnostic instruments are used for clinical diagnosis and treatment of tumor, including the application of staining endoscopy and magnifying endoscopy, which also improve the early diagnosis rate of gastric cancer, and the early diagnosis of tumor will become easier in the near future.