Background: Both diabetes mellitus (DM) and chronic renal insufficiency (CRI) is associated with poor outcomes after percutaneous coronary intervention (PCI) even in the drug-eluting stent (DES) era. The aim of this study is to evaluate whether the combined CRI can be an additional poor prognostic factor in diabetic patients (pts) with chronic total occlusion (CTO) undergoing PCI with DESs. Methods: A total 91 consecutive diabetic pts who underwent PCI for CTO lesions were enrolled for the study. Study population was divided into two groups; diabetic group (n=78) and diabetics with combined CRI (n=13). CRI was defined as baseline serum creatinine more than 1.5 mg/dl. Baseline clinical characteristics, procedure related complications and major clinical outcome were compared between the two groups. Results: Baseline clinical characteristics & procedural details were similar between the two groups. Some of procedure related complications including the incidence of congestive heart failure, myocardial infarction (MI) and in-hospital mortality were higher in diabetic CRI group. At one year follow up, the incidence of total death and Q-MI were higher in diabetic CRI group (Table). Conclusions: Diabetic pts with CRI underwent PCI for CTO lesions were associated with higher rate of procedure related complications and worse clinical outcomes at one year follow up even in the DES era.