Background and Objectives: We sought to evaluate the impact of renal dysfunction on long-term major adverse clinical events (MACE) in patients who underwent percutaneous coronary intervention (PCI). Subjects and Methods: A total of 581 patients (mean age 60.5짹10.6 years) who underwent PCI were divided into two groups according to estimated glomerular filtration rate (eGFR) at admission; group 1 (n=491) has eGFR ��� 60 mL/min/1.73m², group 2 (n=90) has eGFR < 60 mL/min/1.73m². MACE including death, myocardial infarction and stroke during median follow-up of 46 months was evaluated. Results: The patients with renal dysfunction were older (67.3짹8.9 yrs vs. 59.3짹10.4 yrs, p=0.011) and had higher prevalence of female gender (57.8% vs. 30.8%, p<0.001), diabetes mellitus (47.8% vs. 28.5%, p<0.001), hypertension (73.3% vs. 52.1%, p<0.001) and multi-vessel disease (68.9% vs. 52.3%, p=0.004) than the patients without renal dysfunction. The patients with renal dysfunction had higher fasting blood sugar level (145.8짹81.6 mg/dL vs. 135.5짹62.9 mg/dL, p=0.002), lower total cholesterol level (161.9짹62.7 mg/dL vs. 177.8짹43.3 mg/dL, p=0.030) and higher serum creatinine level (1.63짹1.24 mg/dL vs. 0.92짹0.16 mg/dL, p<0.001) the patients without renal dysfunction. MACE was significantly higher in patients with renal dysfunction than without renal dysfunction (hazard ratio (HR) 2.34, 95% confidence interval (CI) 1.31, p=0.004). Multivariate Cox-regression analysis with enter method showed that independent predictor of MACE were multi-vessel disease (HR 2.93, 95% CI 1.39-5.00, p=0.003), renal dysfunction (HR 2.08, 95% CI 1.08-4.03, p=0.029), low ejection fraction (LVEF < 40%) (HR 2.70, 95% CI 1.04-6.96, p=0.04) and dyslipidemia (total cholesterol > 200 mg/dL) (HR 1.81, 95% CI 1.02-3.23, p=0.044). Conclusion: In an unselected cohort of patients who underwent PCI, renal dysfunction was associated with hard endpoints including death, myocardial infarction and stroke and independent predictor of long-term adverse clinical outcome.