Different people, different conditions need to check the colonoscopy time are different, generally ranging from 2 months to 5 years, the specific examination time need to consult the doctor. 1. Patients with diagnosed intestinal diseases: patients suffering from inflammatory bowel disease, ulcerative colitis and other intestinal diseases need to have regular colonoscopy, and it is generally recommended to have a checkup once every 2 to 3 months. 2. Post-operative patients with intestinal diseases: for patients with malignant lesions such as colon cancer, colorectal sarcoma, etc., it is generally recommended to have a review once every six months after surgery; for patients with benign lesions such as intestinal polyps, tumor polyps, etc., it is generally recommended to have a review once every one year after surgery. 3. Normal population: For normal population physical examination or patient screening for intestinal diseases, it is generally recommended to check once in 1 to 2 years. If the colonoscopy is normal and there are no symptoms of intestinal discomfort, it can be checked once every 3 to 5 years. For different populations and patients with different conditions, the time to do colonoscopy will vary, and it is recommended to consult a specialized doctor before checking the colonoscopy.