Background: An antiplatelet agents is main therapeutics in prevention of thrombo-embolic vascular events. This effect is not only due to its anti-platelet effect but also possibly due to an anti-inflammatory effect. The purposed of the study was to antiplatelet resistant related to the progression of non-culprit lesion(NCL) of patients undergoing percutaneous coronary intervention (PCI). Methods: 263 patients that underwent two coronary angiograms with a time interval greater than 9 months were enrolled. All patients underwent PCI (percutaneous coronary intervention) and received antiplatelet agents (aspirin, clopidogrel). The aspirin and clopidogrel resistance are measured by VerifyNow-P2Y12TM assay with second angiography. Aspirin resistance was defined as an ARU (aspirin reaction units) ���550, and clopidogrel resistance was defined as platelet inhibition <20%. Results: 30 (11.4%) patients showed aspirin resistance, 96 (36.5%) patients for clopidogrel resistance and 19 (7.2%) patients for dual resistance. Antiplatelet resistance group had high frequency of cardiac events (myocardial infarction, CVA, TLR and non-TLR) (Table 1). Multivariate analysis, dual resistance was the only independent predictor of non-TLR (odds ratio, 5.01; 95% confidence interval, 1.80 to 13.93; p = 0.002]. Conclusions: In this study, dual antiplatelet resistance was an independent predictor of non-TLR in patients following coronary angiography(Table 2).