Atrophic gastritis is a chronic gastric disease in which the epithelium of the gastric mucosa suffers repeated damage, leading to atrophy of the intrinsic glands, with or without intestinal metaplasia, or pseudopyloric glandular metaplasia. Since most patients with chronic gastritis do not have any symptoms, it is difficult to obtain an exact incidence. The rate of endoscopic diagnosis of chronic atrophic gastritis in China is 17.7% and pathological diagnosis is 25.8 per 1000. Atrophic gastritis is associated with Helicobacter pylori infection, which is currently about 52.2% in China, so the infection rate increases with age. In addition to H. pylori infection, autoimmune gastritis can also lead to gastric mucosal atrophy, and about 20% of people aged 50-74 are positive for anti-mural cell antibodies, and the prevalence of chronic atrophic gastritis is higher in areas with a high incidence of gastric cancer than in areas with a low incidence of gastric cancer.