Aim To observe the effect of CYP2C19 681G>A and 636G>A (CYP2C19*2 and *3) polymorphisms on residual platelet reactivity and adverse clinical events in clopidogrel-treated survivors after percutaneous coronary intervention (PCI). Methods 202 patients with coronary heart disease who received PCI and treated with clopidogrel were enrolled in our study from Jun 2011 to Dec 2011. Based on the number of the CYP2C19 mutation allele, patients were divided into normal group(n78, CYP2C19 *1/*1), one mutation allele group(n100, CYP2C19 *1/*2、CYP2C19 *1/*3) and two mutation alleles group(n24, CYP2C19 *2/*2、CYP2C19 *2/*3). Baseline data, residual platelet reactivity, major adverse cardiac events and bleeding within half a year were observed. Results There was no significant difference on baseline data among the groups besides Calcium channel blocker (normal group, one mutation allele group, two mutation alleles group: 15.4%, 29.0% and 45.8%, P0.007). Adenosine diphosphate induced platelet aggregations had no difference among all groups，no matter within 5 days(normal group, one mutation allele group, two mutation alleles group: 51.60%±17.21%, 55.89%±14.92% and 62.00%±9.75%, P0.060) or 3 months(normal group, one mutation allele group, two mutation alleles group: 49.45%±16.90%, 55.98%±19.03%, 57.64%±18.42%, P0.248). The incidence of nonfatal myocardial infarction was higher in two mutation alleles group than the other groups(normal group, one mutation allele group, two mutation alleles group: 0%, 0% and 8.3%, P0.001) whereas, the incidence of angina recurrence, stent thrombosis, acute heart failure, cardiac death and the bleeding had no difference among all groups. Conclusion Among the patients who received PCI and treated with clopidogrel, CYP2C19 681G>A and 636G>A polymorphisms appear to affect prophase residual platelet reactivity and cardiovascular events.