Background; Effective antiplatelet regimen is an emerging issue in the drug-eluting stent (DES) era. Recent studies indicate that triple antiplatelet therapy using one more antiplatelet agent in addition to aspirin and clopidogrel may have roles in prevention of thrombotic complication after DES implantation. Triflusal is a derivative of salicylate and has been used for secondary prevention of cerebral infarction. We compared the clinical outcomes of dual (aspirin +clopidogrel) and triflusal based triple (aspirin+clopidogrel+triflusal) antiplatelet regimens in patients with complex coronary intervention using DESs. Method & Results; From Feb 2003 to Jan 2006, 498 patients (1259 lesions) who underwent left main or multivessel stenting were selected from our database. The composite outcome of death, myocardial infarction (MI) and nonhemorrhagic stroke within six months was analyzed. Triple group (148 patients, 425 lesions) had more male patients (77.0% vs. 62.0%, p=0.001) and lower cholesterol level (182.4짹41.7 vs. 171.5짹36.0mg/dL,p<0.01) than dual group (350 patients, 834 lesions). Triple group received more stents (1.30짹0.56 vs. 1.18짹1.43 per lesion, p<0.001). Stent length was longer (33.8짹16.4mm vs. 28.6짹13.1mm, p<0.001) and stent diameter was larger in the triple group (3.07짹0.37mm vs. 2.99짹0.37mm, p<0.001). Other baseline clinical and angiographic characteristics were not different between two groups. Seven patients (5.0%) in the triple group and ten patients (2.9%) in the dual group showed composite outcomes within six months (p=0.29). In the multivariate analysis including angiographic and clinical characteristics, there were no differences in the composite outcome between two groups (p=0.13). Conclusion; Triple therapy based on triflusal did not show clinical benefit in preventing atherothrombotic complication over conventional dual therapy in patients undergoing high risk interventions using DES.