Backgrounds: The optimal loading dose of clopidogrel in undergoing percutaneous coronary intervention (PCI) in patients (pts) with angina or non–ST segment elevation acute coronary syndrome, specifically in Asian population is not fully investigated yet. We compared bleeding and vascular complications, 6-month outcomes of pts who received two different clopidogrel loading dose either 300- or 600-mg. Methods: A total 780 consecutive pts (Age; 64.09 짹 10.89, Men; 65.0 %) who underwent PCI with drug-eluting stents (DESs) due to angina or non-ST segment elevation myocardial infarction (MI) were enrolled. ST elevation MI (STEMI) Pts underwent primary PCI were excluded. Pts were divided into the standard dose group (300-mg, n=542 pts) and the high dose group (n=238 pts). The bleeding and vascular complications, angiographic and clinical outcomes up to 6-month were compared between the two groups. Results: Baseline clinical and procedural characteristics were similar between the two groups. In-hospital bleeding and vascular complications were similar between the two groups. At 6-month, angiographic outcomes including late loss (LL) and follow up minimal luminal diameter (MLD) were better in standard dose group compared with those of high dose group (Table). Although the incidence of mortality, MI and major cardiac adverse event (MACE) were similar between the two groups, target lesion and vessel revascularization (TLR and TVR) were higher in the high dose group (Table). Conclusion: Excluding STEMI pts undergoing primary PCI, the 300-mg loading dose of clopidogrel in a series of Asian pts undergoing elective PCI with DES appears to be safe and more effective in reducing repeat PCI as compared with the 600-mg loading dose.