Atrophic gastritis is a type of chronic gastritis that is characterized by atrophy of the mucosal epithelium and glands of the stomach, with a decrease in the number of glands and a thinning of the gastric mucosa. It may also be accompanied by intestinal epithelial metaplasia and atypical hyperplasia of the gastric mucosa. The common causes of chronic atrophic gastritis are: 1. Bad habits, such as smoking, drinking alcohol and spicy food, can lead to atrophy of the gastric mucosa. 2. Helicobacter pylori infection is the main cause of chronic atrophic gastritis. This is because of the long-term growth of Helicobacter pylori in the gastric mucosa, which leads to a decrease in the function of the gastric mucosa, atrophy and reduction of glands, etc. 3, immune factors, physical factors and radiation, etc., can also lead to chronic atrophic gastritis. 4, chronic superficial gastritis can also develop into chronic atrophic gastritis. If chronic atrophic gastritis develops intestinal epithelial hyperplasia, or atypical hyperplasia, it may become cancerous, so it should be reviewed regularly for timely treatment.