Background: Diffuse coronary artery disease remains a clinical therapeutic challenge. With the introduction of drug-eluting stent (DES) diffuse long lesion can be treated more frequently by multiple overlapping DES. The purpose of this study to determine the safety and efficacy of overlapping DES in patients with diffuse coronary artery disease. Methods: All consecutive 87 patients with diffuse coronary artery disease undergoing implantation of minimum of 50 mm long BMS or DES from Jan. 2002 to Dec. 2004 were analyzed. The overlapping stent for dissection without diffuse lesion or combined BMS and DES lesions were excluded. This patients divided two group, BMS group (I: 31 patients, 63.0짹8.2 years), DES group (II: 56 patients, 60.6짹9.3 years). MACE [death, myocardial infarction, target vessel revascularization (TVR), CABG] was evaluated during 6-month clinical follow-up. Results: The number of stents implanted per patient was 2.2짹0.4 in group I and 2.1짹0.3 in group II, whereas the mean total stent length was 61.2짹9.1 mm in group I and 61.3짹9.1 mm in group II (p=NS). Procedural success was achieved in 90.3% in group I and 98.2% in group II (p=0.127). No acute stent thrombosis were observed in both groups. All patients had clinical follow-up (duration: 15짹8.7 months), and 50 patients (57.5%) had angiographic follow-up at six months. Total MACE (including in-hospital) were four death, three MI, fourteen TVR, one CABG in group I and two death, four MI, six TVR in group II. The TVR rates of group II were significantly lower than in group I (10.7% vs. 45.2%; p=0.000). Subacute or late stent thrombosis was developed one in group I (3.2%) and two (3.6%) in group II. Conclusions: The implantation of overlapping DES for diffuse long coronary lesion is safe and associated with good clinical outcomes.