The time for gastric disease to develop gradually into gastric cancer varies from person to person. Some people may have Helicobacter pylori infection, or often smoke, drink alcohol, have bad living conditions, or not pay attention to their diet, gastric disease progresses relatively fast, and some patients may develop gastric cancer in 2-3 years. If there is a gastric ulcer that does not heal, accompanied by atypical hyperplasia, and there is a family history or genetic history, the time to develop cancer may be 1-2 years. For chronic gastritis, gastroesophageal reflux disease (GERD) and localized erosion of the stomach, the chance of gastric cancer is relatively low. If these diseases are repeatedly prolonged, after 3-5 years, some people may develop gastric cancer in more than a decade, provided that it is also prolonged and accompanied by Helicobacter pylori infection. In conclusion, the development of gastric disease to gastric cancer varies and needs to be analyzed on a case-by-case basis according to physical fitness, living environment, living habits, and whether one has a genetic family history. As long as systematic and comprehensive treatment is given, frequent follow-up gastroscopy and anti-Helicobacter pylori treatment, most gastric diseases basically will not develop into gastric cancer.