Background: Although cilostazol and drug-eluting stenting for patients with diabetes mellitus have provided a better clinical outcome, it is not known whether this effect occurs in diabetic patients with chronic total occlusion (CTO). Methods and Results: We analyzed the three-year outcome of 143 diabetic patients with CTO successfully treated with either sirolimus-eluting stent (n = 65) or paclitaxel-eluting stents (n = 78) and compared triple antiplatelet therapy (aspirin, clopidogrel, and cilostazol, triple group, n = 61) and dual antiplatelet therapy (aspirin and clopidogrel, standard group, n = 82). During an overall follow-up period of three years, the triple group had fewer MACE, including death, myocardial infarction or target lesion revascularization, than the standard group (1.7% vs. 27.4%, log-rank p = 0.031). One patients died in the standard group, eight myocardial infarctions occurred in the standard group while one myocardial infarction in the triple group (log-rank p = 0.089); and target lesion revascularization was performed in eleven patients in the standard and one in the triple group (log-rank p = 0.047). Regarding insegment late loss, no significant difference was apparent between the triple and the standard group(0.38 짹 0.52 mm vs. 0.48 짹 0.64 mm, p = 0.53). Conclusions: In patients with diabetes mellitus and CTO, use of cilostazol is associated with improvement of long-term outcome.