Abstract: ObjectiveTo observe the incidence and the influential factors of clopidogrel resistance (CPGR) in patients who received percutaneous coronary interventions(PCI). MethodsEighty six patients with PCI were subjected to the study. Light transmittance aggregometry was used to measure platelet aggregation (PA) induced by adenosine diphosphate (ADP) before and 5-7 days after clopidogrel intake. The △P measurements were based on the standard of △P ≤ 10% CPGR (negative values included) . The patients were divided into CPGR group and none CPGR group according to the △P. The relation between CPGR and the patients’ relevant clinical biochemical indexes was observed. Results