Objective To evaluate the effects of hemoclips on preventing delayed bleeding for early gastric cancer (EGC) after endoscopic submucosal dissection (ESD). Methods Clinical data of 459 patients who underwent ESD for EGC in Beijing Friendship Hospital from June 2013 to August 2020 were collected retrospectively. Patients were divided into group A (hemoclip group, n=162) and group B (non-hemoclip group, n=297) according to whether preventive hemostatic clip treatment was performed after resection. Delayed bleeding within 2 weeks after ESD was observed. Univariate analysis and subgroup analysis were conducted for the delayed bleeding incidence and clinicopathological features. Results Delayed bleeding incidences of group A and group B were 3.1% (5/162) and 8.1% (24/297) with significant difference between the two groups (χ2=4.418, P=0.036). Subgroup analysis showed that there were significant differences in the delayed bleeding incidence between the two groups when the diameter of the tumor >20 mm [3.5% (2/57) VS 15.3% (13/85), χ2=5.016, P=0.025], the tumor located in the lower part of the stomach [1.0% (1/97) VS 10.4% (20/192), χ2=8.425, P=0.004], and the depth of tumor invasion was M/SM1 [3.2% (5/157) VS 8.1% (23/285), χ2=4.072, P=0.044]. There were no significant differences in the delayed bleeding incidence between group A and group B when the diameter of the tumor ≤20 mm, the tumor located in the upper/medial part of the stomach and the depth of tumor invasion was SM2 (P>0.05). Conclusion Hemoclips can prevent delayed bleeding after ESD for EGC, which is mainly observed in a tumor of diameter >20 mm, located in the lower part of the stomach and M/SM1 tumor invasion. It has little effect on the prevention when the tumor diameter ≤20 mm and located in the upper/medial part of the stomach.