Background and Aim. Patients with chronic dialysis dependency undergoing percutaneous coronary intervention (PCI) are at a greater risk of hemorrhagic and ischemic events. Due to their exclusion from randomized clinical trials, the optimal antithrombotic regimen for this population remains unknown. Bivalirudin has been associated with fewer hemorrhagic complications than unfractionated heparin (UFH) in patients undergoing PCI. We evaluated major adverse cardiac event (MACE) and hemorrhagic event rates for an antithrombotic regimen using bivalirudin or UFH during PCI in acute coronary syndrome (ACS) patients with chronic dialysis dependency. Methods. A retrospective study was performed, including 211 patients on dialysis undergoing PCI due to ACS from January 2014 to April 2019 at the China-Japan Friendship Hospital. Patients were divided into 2 groups based on anticoagulation regimen: the bivalirudin group (86 cases) or the UFH group (125 cases) during and after PCI. Statistical analyses were used to compare MACE and hemorrhagic events between groups at 30 days after PCI. Results. No patients experienced stent thrombosis within 30 days after PCI regardless of anticoagulant. There was no difference in the incidence of MACE in the bivalirudin group compared with the UFH group (6.98% vs 8.80%, respectively; P>.05). The rate of hemorrhagic events in the bivalirudin group was significantly lower than in the UHP group (5.81% vs 18.4%, respectively; P<.05), particularly for rates of mild bleeding (4.65% vs 15.2%, respectively; P<.05). There were no significant differences in rates of severe bleeding between the bivalirudin and UFH groups (1.16% vs 4.00%, respectively; P>.05), although fewer severe hemorrhagic events occurred in the bivalirudin group. Conclusion. Bivalirudin was associated with fewer bleeding events following PCI in individuals with end-stage renal disease on dialysis.