Background: Drug-eluting stent (DES) has been proven its efficacy in randomized trials, and the penetration rate is increasing rapidly. Therefore, we investigated whether the use of DES has changed clinical outcomes of patients undergoing percutaneous coronary intervention (PCI) in real world. Methods: From January 2002 to March 2005, 2300 consecutive patients were treated with DES (N=1064) or bare metal stent (BMS) (N=1186) and registered in SMART (Samsung Medical center Angioplasty RegisTry) database. At the present writing, six-month clinical follow-up was completed in 1508 patients (66%) and survival analysis was performed for this population. Results: There was no difference of clinical parameters between two groups. Although there was no difference of cardiac death rate between two kinds of stents, Major adverse events (MACE)-free survival rate at 6 month and 1 year was significantly lower in DES (96.2%, 91.7%) than in BMS (91.9%, 84.5%)(log-rank p < 0.001), respectively. Revascularization-free survival rate at 6 month and 1 year was also significantly lower in DES (98.0%, 94.2%) than in BMS (93.4%, 86.0%) (log-rank p=0.001), respectively. Conclusion: Although non-randomized nature of this study, our results show that DES implantation improved clinical midterm result of PCI in daily practice. A more detailed result would be shown at the meeting.