Background: CREST study showed significant decrease in the restenosis rate in the cilostazol group compared with the control group after bare-metal stenting. It is uncertain that cilostazol is also effective in restenosis reduction after drug eluting stents (DES) implantation. We performed a prospective randomized study to evaluate the effect of long-term administration of cilostazol after DES on the top of aspirin and clopidogrel. Methods: From June 2004 to December 2004, 210 consecutive patients with 268 lesions were randomized after DES stenting to receive aspirin and clopidogrel plus cilostazol(group I, n=105) or aspirin and clopidogrel (Group II, n=105) for 6 months. The primary end point was in-segment restenosis at 6 months and the secondary end points included late loss, major adverse cardiac events, stent thrombosis. Results: The baseline clinical and angiographic characteristics were similar between two groups. One procedure-related death occurred in Group II. During the follow-up, there were no other events except one sudden cardiac death. Six-month angiographic follow-up was performed in 76% of eligible patients. The angiographic in-segment restenosis and late loss were not different between 2 groups (Table 1). The target lesion revascularization rate was 3.2%. Conclusions: This study showed favorable clinical outcomes of triple and dual antiplatelet therapy after DES implantation. There was no significant synergy of DES and cilostazol in restenosis reduction.