Objective: To evaluate the long-term clinical outcomes after percutaneous coronary intervention (PCI) with drug-eluting stents (DES) for ostial/shaft lesions in patients with unprotected left main coronary artery (ULMCA). Method: A total of 271 patients with isolated ostial/midshaft lesions in unprotected left main coronary artery who received drug-eluting stents (DES) implantation between January 2003 and July 2009 in Beijing An Zhen Hospital were consecutively enrolled . The endpoints of the study were all-cause death, repeat revascularization, myocardial infarction (MI) and stroke. Cox regression was carried out to analyze the all-cause mortality. Meanwhile, multivariate logistic regression analysis was performed to determine the independent risk factors of all-cause death. Results: The mean age of the patients was (62±10) years, and 201 of them (74.2%) were male. The median follow-up was 12.5 years (interquartile range: 10.1-14.5 years). During the follow-up, 46 patients (17.0%) died, of whom 20 (7.4%) died of a cardiovascular cause. A total of 38 (14.0%) cases suffered a MI, and 15 (5.5%) cases suffered a stroke. Repeat revascularization was performed in 63 (23.2%) cases. Multivariate logistic regression analysis showed that age (HR=1.041, 95%CI: 1.003-1.081, P=0.033), creatinine (HR=1.028, 95%CI:1.014-1.042, P<0.001) and diabetes mellitus (HR=1.924,95%CI: 1.053-3.514, P=0.033) were independent risk factors of all-cause death, whereas left ventricular ejection fraction (LVEF) (HR=0.972, 95%CI:0.953-0.992, P=0.007) was a protective factor. Conclusions: During a median follow-up of 12.5 years, the prognosis of PCI for left main ostium/shaft lesion was good. Age, creatinine and diabetes mellitus are independent risk factors of all-cause death.