There is no exact fixed time for how often gastroscopy should be done. It is generally recommended that it should be done around 3 months to 3 years, and how often it should be done should be based on your own disease and the symptoms you experience. 1. Gastric ulcer: gastric ulcer has a certain tendency of malignant change, so it is recommended to do gastroscopy about 3 to 6 months. 2. Atrophic gastritis: Atrophic gastritis is a kind of chronic digestive disease, which has a certain chance of becoming cancerous, so it is recommended to have a gastroscopy in about 1 to 2 years if atrophic gastritis is detected. 3. Heavy heterogeneous hyperplasia of gastric mucosa or carcinoma in situ: this is a more serious condition, and it is recommended to do gastroscopy once in 3 months. Besides, if there is a family history of esophageal cancer or gastric cancer, it is recommended to do gastroscopy before 40 years old, and then depending on the specific situation, it is generally recommended to do gastroscopy once every 2 to 3 years. If you have any symptoms of discomfort, you should go to the hospital and consult your physician for guidance.