OBJECTIVE：To investigate the correlation between CYP2C19 gene polymorphisms and antiplatelet reactivity of clopidogrel in Xinjiang Uygur patients with acute coronary syndrome （ACS）. METHODS ：Totally 90 Uygur patients with ACS who were admitted to the cardiovascular department of Xinjiang Kashi Second People ’s Hospital from Jan. 2018 to Jan. 2019 were selected as the study subjects. They were given anti-platelet therapy of asprin+clopidogrel ，and received the treatment continuously for one year after discharge. The platelet aggregation inhibition （DPAI）rate of the patients were determined ，and the response to clopidogrel was evaluated. PCR-fluorescence probe method was used to detect genotype of CYP2C19*2 and * 3，and PCR-direct sequencing method was used to detect genotype of * 17. Multivariate Logistic regression analysis was adopted to investigate the correlation of gene and non-gene factors with DPAI of patients. RESULTS ：Among 90 patients，there were 10 patients with clopidogrel resistance （CR）and 80 patients with non-CR. There were 58，28 and 4 patients with CYP2C19*2 G/G，G/A，A/A genotype，respectively；there were 88 and 2 patients with CYP2C19*3 G/G，G/A genotype ，respectively；there were 64 and 26 patients with CYP2C19*17 C/C，C/T genotype ，respectively；the genotype frequency of each genotype was consistent with Hardy-Weinberg equilibrium （P＞0.05）. After treatment ，DAPIs of patients with CYP2C19*2 G/A，A/A genotype were decreased significantly，while those of the patients with A/A genotype were significantly lower than patients with G/A genotype patients （P＜ 0.05）. DAPIs of patients with CYP2C19*17 C/T genotype were increased significantly ，compared with C/C genotype 2016D01C087） patients （P＜0.05）. There was no statistical significance in @fudan.edu.cn DAPIs between CYP2C19*3 G/A and A/A genotype patients （P＞0.05）. Multivariate Logistic regression analysis showed 85775264@qq.com that CYP2C19 gene pol ymorphism was independently related to DPAI in Xinjiang Uygur patients with ACS [OR ＝2.314，95％CI（1.569，3.144），P＝0.009]，while age ，gender，smoking and other non-gene factors were not related to DPAI （P＞0.05）. CONCLUSIONS ：CYP2C19 gene polymorphism is associated with antiplatelet reactivity of clopidogrel in Xinjiang Uygur patients with ACS. * 2 wild type patients may have higher DPAI ，while * 17 wild type patients may have lower DPAI.