It is usually necessary to fast for 8 hours before gastroscopy and make sufficient preparation to ensure the examination goes smoothly. Fasting before gastroscopy, with food in the stomach will affect the doctor’s diagnosis, and may also cause nausea, vomiting and other adverse symptoms during the examination. The time for complete emptying of stomach contents is about 4~6 hours. In order to ensure the smooth running of the examination, as well as the accuracy of the examination results, it is necessary to fast for 8 hours before the gastroscopy examination, and water should also be prohibited. Before the gastroscopy should be detailed and physician to communicate personal situation, so as to avoid the existence of gastroscopy contraindications; if there are dentures, the dentures should be removed before the examination; if you are more worried about the pain, you can carry out painless gastroscopy to reduce the sense of pain. Gastroscopy should choose a regular hospital, conducive to the diagnosis and treatment of the condition.