On the day of gastroenteroscopy, you can eat some light, easy-to-digest fluid or semi-fluid food, such as millet porridge, rice paste, egg custard, etc., and pay attention to chewing and swallowing slowly. Gastroscopy and colonoscopy are both invasive tests, you can’t eat immediately after the test, you need to fast and abstain from food and water for a period of time. If the patient is only an ordinary gastroenteroscopy, generally need to fasting and water fasting for two hours, after two hours you can drink a small amount of warm water, if there is no discomfort, you can gradually open the diet. If the patient does gastroenteroscopy and biopsy at the same time, it is necessary to fasting and water fasting for 4~6 hours. The diet on the day after gastroenteroscopy should be kept light, and the main focus is on fluid and semi-fluid diet with no or little slag, such as millet porridge, rice paste, egg custard, rotten noodles, noodle soup, etc. If there is no obvious discomfort after eating, it can be gradually transitioned to a normal diet on the next day. After gastroenteroscopy, patients should avoid eating cold, spicy, greasy and other stimulating or indigestible food and strong tea, strong coffee and so on. At the same time, pay attention to rest, ensure enough sleep, avoid staying up late, quit smoking and drinking. After gastroenteroscopy, patients should strictly follow the doctor’s instructions for dietary management, and gradually return to normal diet, if there is obvious discomfort during eating, it is recommended to consult a doctor in time to avoid delaying the condition.