In gastroenterology clinics, it is common to encounter patients who give up or refuse gastroscopy because they are afraid of the test or do not know why they need it. If they are suffering from stomach pain or bleeding, then most of them would be willing to cure the disease and undergo gastroscopy, but for people with less obvious or mild symptoms, they are not so happy to accept it. However, China is a country with high prevalence of stomach cancer, which occurs in middle-aged and elderly people, and there are no specific symptoms in early stage of stomach cancer, so one of the purposes for doctors to advise patients to have gastroscopy is to exclude whether the symptoms are caused by stomach cancer. Gastroscopy is the best way to detect early gastric cancer. China is a country with high prevalence of gastric cancer, more than half of the new gastric cancers in the world are in China, compared with Korea and Japan, our early gastric cancer rate is very low, and most of the patients are already in the middle and late stage when they are found, so the treatment effect is greatly reduced; while Korea and Japan are also countries with high prevalence of gastric cancer, but their early detection rate is very high, which makes the cure rate much higher, mainly because of the popularity of gastroscopy in Korea and Japan. This is mainly because of the popularity of gastroscopy in Korea and Japan. The early manifestation of gastric cancer is very secretive, the first may only be a little change in the color of gastric mucosa, and the current technology such as CT and ultrasound cannot capture such a small change, while gastroscopy combined with visual observation and pathological analysis can make accurate judgment on early gastric cancer and precancerous lesions. That’s why in gastroenterology, doctors will suggest gastroscopy for those who are old and have not had gastroscopy according to their medical history, and gastroscopy can exclude or detect gastric cancer at an early stage.