H. pylori infection is a causative factor of gastric cancer, but it does not always lead to gastric cancer; a few patients may develop cancer, and the process may take years, decades or even decades, with an average of more than ten years. H. pylori can not only promote the conversion of nitrate into nitrite and nitrosamine, but also cause chronic inflammation of gastric mucosa, which can accelerate the overproliferation of mucosal epithelial cells and lead to carcinogenesis if combined with other pathogenic factors such as geographical environment, diet and living habits, genetics, etc. In addition, the toxic products of H. pylori may also have cancer-promoting effects. Therefore, H. pylori infection should be treated in a timely manner to avoid prolonging the disease process and leading to gastric cancer. Since H. pylori can be transmitted through the digestive tract, it is recommended that families with H. pylori infected patients eat a separate meal system and develop good dining habits.