Chronic gastritis may be caused by Helicobacter pylori infection, autoimmunity, and age factors. 1. Helicobacter pylori infection: It may be caused by using the same tableware with patients infected with Helicobacter pylori and not washing hands before meals. After entering the human body, H. pylori can colonize the gastric mucosa. And can produce a variety of enzymes, including urease, proteolytic enzymes, catalase, etc., thus causing inflammatory damage to the gastric mucosa, and then chronic gastritis. 2. Autoimmune: mainly refers to the body to attack its own gastric wall cells, destroying the gastric mucous membrane barrier, gastric mucous membrane damage, which can cause chronic gastritis. 3. Age factor: the elderly gastric mucosa can appear degenerative changes, can make the gastric mucosa repair and regeneration function is reduced, chronic inflammation, epithelial proliferation abnormalities and gastric gland atrophy, which can appear chronic gastritis. There are other reasons that may lead to chronic gastritis, it is recommended that patients diagnosed with chronic gastritis go to the hospital in a timely manner, and follow the doctor’s instructions for treatment, to avoid delaying the condition.