The dietary contraindications of colonoscopic polypectomy need to be guided separately according to different types of treatment. 1, for simple and small polypectomy, normal diet is sufficient; 2, for partial removal of larger polyps, including ESD and EMR treatment, routine fasting is required for three days, and patients should minimize water intake to avoid bleeding from the wound surface and infection caused by intestinal flora activity through extra-gastrointestinal nutrition and reduction of gastrointestinal motility. The patient’s diet should be liquid. After starting the diet, choose a liquid diet in the early stage, and after the patient’s gastrointestinal tract adapts, he can enter a semi-liquid diet, and then gradually transition to a normal diet, eat more digestible food such as vegetables, rotten noodles, porridge, etc., reduce spicy and greasy food, do not drink alcohol, smoke, usually in about a month after surgery, all patients can return to a normal diet.