ObjectiveTo explore the prophylactic effect of clipping after endoscopic mucosal resection(EMR) of sessile colorectal polyps of diameter below 10 mm on delayed post-polypectomy bleeding (DPPB). MethodsPatients with sessile colorectal polyps of below 10 mm undergoing EMR from January 2017 to December 2019 in Digestive Disease Hospital,Heilongjiang Provincial Hospital were randomly divided into the clipping group (group A) and the non-clipping group (group B) by random number table, and DPPB rates of both groups were compared. ResultsA total of 1 838 patients were included, 912 patients in group A and 926 patients in group B. The incidences of DPPB were 1.00% (9/912) and 1.10% (10/926) respectively, with no significant difference (χ2=0.039， P>0.05).The proportion of bleeding polyps were 0.44%（9/2 029）and 0.49%（10/2 025） respectively, with no significant difference (χ2=0.055， P>0.05). Polyp of 6-9 mm （OR=11.032， 95%CI：2.545-47.821， P＜0.05） was the independent risk factor for delayed bleeding in small sessile colorectal polyps after EMR. ConclusionProphylactic clipping for sessile colorectal polyps below 10 mm after EMR may not significantly reduce the risk of DPPB.