Patients who met the criteria for removal of 10-19mm colorectal polyps using cold snare or hot snare were included in the study, signed by endoscopic treatment written informed consent for surgery, patients with detailed tracking and record the basic information and information related to the operation, postoperative lack of region and edge endoscopic observation carefully no residue, additional excision may be took if necessary，after resection specimen inspection, and in 6 months review colonoscopy, assess whether there is residual or recurrence of polyps.Main outcome: technical success rate (no other auxiliary resection), complete resection rate, secondary outcome: intraoperative and postoperative complications, polypectomy time and related costs, influential factors of incomplete resection.Research significance: The effectiveness, safety and cost-effectiveness of cold and hot snare resection of 10-19mm colorectal polyps were compared, and the influencing factors of incomplete polyps resection were analyzed, so as to provide evidence for the decision on the best method of medium-size polyps resection.

Inclusion Criteria:

1. colorectal polyps sized 10≤ diameter ≤19 mm;
2. Boston bowel prepare score: 5-9;
3. The patients all signed the informed consent of endoscopic treatment.

Exclusion Criteria:

1. Complicated with inflammatory bowel disease, P-J syndrome or familial polyposis;
2. Complicated with malignant tumors;
3. polyp size is uncertain;
4. Currently taking aspirin, warfarin or other anticoagulants.

Patients who met the criteria for removal of 10-19mm colorectal polyps using cold snare or hot snare were included in the study.