Background: Distal bifurcation involvement has been regarded as a major predictor for adverse clinical outcomes in patients who underwent percutaneous or surgical revascularization for unprotected left main coronary artery (ULMCA) disease. Methods: Between Jan, 2000 and June, 2006, a total of 2311 patients with ULMCA stenosis were enrolled from 12 academic centers in Korea. Percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) were performed in 1141 patients and 1170 patients, respectively. Results: Bifurcation stenosis at ULMCA was identified in 1106 patients (50.4%). Patients with distal bifurcation involvement had significantly higher risk clinical and procedural profiles (old age, male gender, history of angioplasty, MI or stroke, hypertension, smoking, hyperlipidemia, unstable angina) than those without bifurcation stenosis. During median follow-up of 37.5 months, bifurcation involvement was not associated with long-term morality. However, bifurcation involvement was significantly associated with increase of target vessel revascularization in patients undergoing PCI, not CABG (Table). Conclusions: In patients with ULMCA disease, bifurcation disease was not related with an increased mortality. However bifurcation involvement was associated with more frequent repeat revascularization in patients undergoing PCI, but not in patients undergoing CABG.