Background: Chronic total occlusion (CTO) intervention is still challenging because of the limited procedural success rate and higher target failure. The detailed safety and efficacy data of CTO intervention in the drug-eluting stent (DES) era from multi center real world registry are still limited. Methods: Korean multicenter retrospective CTO registry was collected from Jan 2007 to Dec 2009 and a total of 2961 patients (pts) underwent CTO intervention with DESs were enrolled from 26 major percutaneous coronary intervention (PCI) centers by filling out retrospective case report form (CRF). Baseline clinical and procedural characteristics, major clinical outcomes up to 12 months were evaluated. Results: The baseline clinical characteristics showed that male were in 73.9%, previous myocardial infarction (MI) 83.5%, previous PCI 20.5%, hypertension 60.0%, diabetes 35.0%, hyperlipidemia 31.1% and current smoker 26.3%. Myocardial viability test was done in 13.1% and pre-PCI cardiac CT was done in 15.6%. Lesion distribution was as follows; RCA 43.0%, LAD 40.6%, LCX 21.8%, LM 0.6% and Ramus 0.4%. Angiographically unfavorable morphology was in 64.5%. Anterograde approach was attempted in 96.5% and IVUS guided intervention was done in 25.4%. More than 90% of the pts received DESs; Sirolimus-eluting stents (SES) 35%, Paclitaxel-ES (PES) 26%, Zotarolimus-ES (ZES) 22%, Everolimus-ES (EES) 11% and others 6%. Overall procedural success rate was 81.6% (2074/2538 pts) At 12 months, total death was 2.9%, any MI 1.3%, target lesion revascularization (TLR) 4.4%, target vessel revascularization (TVR) 7.0%, TLR-major adverse cardiac events (MACEs) 6.5%, TVR-MACE 10.3% and MACCE 10.6% (Table). Conclusions: The success rate, safety profile and 12-month cumulative clinical outcomes of Korean CTO pts following PCI with DES were favorable. Long-term follow up with larger study population will be necessary to elucidate final conclusion.