Background: The influence of SES on the treatment of patients with chronic total coronary occlusions is not well known. The purpose of this study was to evaluate the Safety and Effectiveness of Sirolimus-Eluting Stent for treatment of chronic total coronary occlusions compared with bare metal stent. Methods and Results: A control group (bare metal stent: 45 lesions/ 42 patients) and a Sirolimus-eluting stent group(50 lesions/ 48 patients) with successful PCI for CTO of ���3months of duration were enrolled. Of the enrolled these patients, follow-up coronary angiography in BMS group and SES group was performed in 26 lesions/ 24 patients and 40 lesions/ 39 patients, respectively. The primary end point were angiographic minimal lumen diameter(MLD) and binary restenosis at 3months. Secondary end points were in-hospital outcomes and major adverse cardiac events(MACE) at 9months. The in-stent MLD was significantly greater in the SES group at 2.18짹0.63mm vs. the BMS group at 1.61짹0.67mm ( a 35% increase, p<0.001). Binary restenosis occurred in 2 lesions of 40 SES lesions (5.0%) and 11 lesions of 26 BMS lesions(42.3%, p<0.001). Fewer patients with SES stents had major adverse cardiac events at 9months than did BMS group(15 vs 42.4%, p=0.021), due mainly to a lower need for re-percutaneous coronary intervention. Conclusions: The results of this study support the safety and effectiveness of the SES to prevent high restenosis in the CTOs.