Since 2013, my country released the first edition of "Chinese Guidelines for Intestinal Preparation Related to Diagnosis and Treatment of Digestive Endoscopy (Draft)"[1]Since then, with the in-depth popularization of digestive endoscopy technology in China, intestinal preparation has been paid more and more attention, and related studies have emerged at home and abroad, and many related consensus and guidelines have been published internationally[2,3,4,5,6,7]。 Therefore, in order to further improve the methods and methods of intestinal preparation before endoscopic diagnosis and treatment in China and improve the quality of endoscopic diagnosis and treatment, it is necessary to summarize the relevant research at home and abroad, draw lessons from foreign evidence-based evidence and relevant guidelines, and combine the actual situation in China, and formulate a new version of the guidelines on the basis of the previous edition. In April 2019, the Digestive Endoscopy Professional Committee of Endoscopist Branch of Chinese Medical Doctors Association and the Oncology Endoscopy Professional Committee of Chinese Anti-Cancer Association invited domestic experts in relevant fields to formulate a new version of the Guidelines for Intestinal Preparation Related to Diagnosis and Treatment of Digestive Endoscopy in China, with a view to providing guidance on intestinal preparation related to endoscopic diagnosis and treatment of patients with digestive tract diseases.