Abstract: Objective：To explore the impact of polymorphisms distribution of clopidogrel metabolism related gene CYP2C19 on stent restenosis after percutaneous coronary intervention（PCI） of CHD patients. Methods： 356 patients diagnosed CHD by coronary angiogarphy and successfully underwent PCI treatment from January 2015 to August 2016 in our hospital were enrolled in the study.The postoperative incidence of stent restenosis within 12 months was recorded．Ploymerase chain reaction(PCR) and DNA sequencing methods were used to detect the genotypes of CYP2C19 polymorphisms. We divided the patients into two groups by the result of the genotypes of CYP2C19 polymorphisms， one group was normal metabolize genotypes of CYP2C19 polymorphisms， another group was intermediate and slower metabolize genotypes of CYP2C19 polymorphisms， which had CYP2C19*2 or CYP2C19*3. Results： The basic clinical data(including gender， age，BMI，LDL， HBA1C，systolic pressure，creatinine clearance rate， history of smoking and EF) had no statistical significance between two groups(P>0.05)．We found there was a lower incidence of stent restenosis in patients with normal metabolize types of CYP2C19 polymorphisms than in patients with intermediate metabolize type and poor metabolize types CYP2C19(P<0.05). Conclusion： Patients with coronary artery disease who have CYP2C19*2 or CYP2C19*3 intermediate and slower metabolic genotype have increased incidence of stent restenosis after PCI.