Objective To study the clinical characteristics and prognosis of unprotected left main (Ul-M) coronary artery disease patients with chronic kidney disease after drug-eluting stents ( DKS) implantation. Methods 267 UI.M coronary artery disease patients who has implanted DKS were included in the study from January 2005 to March 2010. Patients were divided into two groups according to their estimated glomerular filtration rate ( EGFR ) : EGFR <60 ml • min-1 • 1.73 min-2(77 patients), and eCFR≥ 60 ml • min-1 • 1.73 min-2( 190 patients) . The clinical parameters and prognosis of ULM patients treated with DKS in different EGFR groups were retrospectively compared. Results In higher EGFR group, left ventricular ejection fraction (LVRF) and morbidity of coronary ostial lesions were higher than the other group. Cerebrovascular diseases ( 13.0% vs 5.3% ) , chronic total occlusion (CTO, 28.6% vs 12.1%), hypertension (70. 1 % vs 53.2% ) were more common in lower EGFR patients ( all P < 0.05 ) . Total mortality and c ardiac mortality were higher in EGFR <60 ml • min-1 • 1.73 m-2 group ( P =0.016,0.006, respectively). Low EGFR level was an independent risk factor after adjusting multiple factors. Conclusion For the lil.M disease patients with reduction in kidney function (EGFR <60 ml • min-1 • 1.73 m-2) , DES should be selected with a careful study considering its increasing risk of death. Chronic renal insufficiency is a risk factor and may predict poor prognosis for patients with UI.M after DKS implantation.