Objective To explore the optimal duration of hemostatic compression after coronary angiography (CAG) or percutaneous coronary intervention (PCI) via the distal radial approach.Methods Patients undergoing CAG (n=515) or PCI (n=515) were randomly assigned to receive hemostatic compression for 2 h,3 h, 4 h, 5 h, and 6 h respectively, after completion of the procedure.Elastic band was used for hemostasis.The effectiveness （incidence of bleeding and hematoma）, safety （incidence of radial artery occlusion, vasovagal reflex, and blister）, and patient feelings （pain and forearm swelling） were recorded.Results No patient deve-loped radial artery occlusion and vasovagal reflex.There were no significant differences in incidence of bleeding and hematoma among five groups in either CAG or PCI patients （both P＞0.05）.Significant differences were seen in the incidence of blister, pain severity and the degree of forearm swelling among five groups in either CAG or PCI patients （all P＜0.05）, but with no significant differences among 2 h, 3 h, and 4 h group (all P＞0.05).Conclusion Shorter duration of hemostatic compression alleviates pain and forearm swelling in patients undergoing CAG or PCI through the distal radial artery, without increasing the incidence of complications.