Abstract: With the development and popularization of endoscopic techniques,  the importance of colonoscopy is further highlighted.And bowel preparation, a prerequisite for colonoscopy,  is particularly significant.In order to improve the method and quality of bowel preparation before the therapeutic endoscopy,  Digestive Endoscopy Special Committee of Endoscopic Physicians Branch of Chinese Medical Association and Cancer Endoscopy Committee of China Anti  Cancer Association  updated the 2013 guide.This article interprets the updated content of Chinese Guideline for Bowel Preparation for Colonoscopy(2019) in order to deepen the clinician's understanding,  and guide patients to do bowel preparation, also to maximize the benefits of patients.

Key words: colonoscopy, guideline, bowel preparation