Background : Successful percutaneous coronary intervention (PCI) of the occluded infarct-related artery (beyond 12 hours after symptom onset) may improve long-term survival. The aim of this study was to identify predictors of major adverse cardiovascular events (MACE) of PCI in latecomers with acute myocardial infarction (AMI). Methods: A total of 751 AMI patients (63.5짹 12.3 years, 67.5% males) enrolled in a nationwide prospective Korea Acute Myocardial Infarction Registry (KAMIR) between Nov. 2005 and Jan. 2008 who presented between 12 hours and 3 months after symptom onset were included in the present study. The study population underwent successful PCI for total occlusion of the infarct-related artery with poor or no antegrade flow (Thrombolysis In Myocardial Infarction flow 0 to I) and all of them had completed one-year clinical follow-up. The primary end point was MACE (death, myocardial infarction, target lesion revascularization) at 12 months. Results: During the one-year follow-up, the primary end point occurred in 92 patients (12.3%). Patients with MACE were older (68.6짹11.7 vs. 62.9짹12.2), had more history of diabetes mellitus (16.2% vs. 10.6%, p=0.036), higher admission serum glucose (189.5짹105.8 vs 158.7짹77.5, p=0.001), creatinine (1.41짹1.59 vs. 1.04짹0.57, p<0.001) values and lower ejection fraction on periprocedural echocardiogram (43.7짹14.0% vs 50.8짹11.6%, p<0.001). On multivariate Cox regression analysis, age ��� 75 (HR 2.62, 95% CI 1.47-4.68, p=0.001), EF ��� 40% (HR 2.83, 95% CI 1.72-4.64, p<0.001), serum creatinine ��� 1.5 mg/dL (HR 2.54, 95% CI 1.33-4.82, p=0.005), systolic BP ��� 100 mmHg (HR 2.30, 95% CI 1.24-4.29, p=0.009) and left main or 3-vessel disease (HR 1.69, 95% CI 1.02-2.79, p=0.04) were independent predictors of the primary end point. Conclusion: Significant predictors of one-year MACE after successful PCI in latecomers with AMI were age, renal insufficiency, systolic dysfunction and complex lesions.