Stomach cancer is already common in our real life, which not only affects people’s normal life and work, but in serious cases, can lead to patients’ death. At present, although there are good treatment effects for leukemia, surgery and drugs have huge toxic side effects on patients, which bring torment and pain to their bodies. Therefore, the prevention of stomach cancer is very important. 1. Quit smoking and alcohol: We all know the harm of smoking, which is inextricably linked with stomach cancer. Smoke contains many carcinogenic or cancer-promoting substances, which is one of the main causes of stomach cancer. Although alcohol itself is not a carcinogenic substance, strong wine will stimulate the gastric mucosa, damage the mucosal tissue and promote the absorption of carcinogenic substances. Drinking alcohol together with smoking is more harmful to the stomach because alcohol can enhance the permeability of the cell membrane, thus strengthening the absorption of carcinogenic substances in smoke. 2.Actively treat chronic diseases: To prevent the occurrence of gastric cancer, we must actively treat chronic diseases of the stomach, such as atrophic gastritis with intestinal epithelial hyperplasia, abnormal hyperplasia, untreated gastric ulcer, gastric polyps, etc. These diseases can further deteriorate into gastric cancer. Therefore, we must pay great attention to these diseases. 3.Supplementary nutrition: We should eat more fresh vegetables, fruits and milk rich in vitamins, which can participate in repairing the natural barrier of the body and improve the immunity of the body to prevent the synthesis of chemical carcinogens in the body. 4.Regular medical checkups: Regular annual comprehensive checkups should be conducted, especially for people with diseases such as gastric acid deficiency, atrophic gastritis and gastric polyps and post-operative gastric cancer patients, who should be highly alert to the occurrence of gastric cancer and strive to achieve early detection, early diagnosis and early treatment. 5.Rational diet: Develop good living and eating habits, eat less or no food containing carcinogenic nitrosamines such as pickled, fried, smoked and baked mold, protect gastric mucosa, eat regularly and quantitatively, avoid overeating, avoid damaging stimulation of stomach by stimulating food, and reduce the chance of gastritis and gastric ulcer. The secret to prevent hypofractionated gastric cancer is very simple, which is to eat alkaline food to prevent the accumulation of acidic waste, because acidified body fluid environment is fertile soil for normal cells to become cancerous.