Abstract: Objective To investigate the effect of clopidogrel guided by thromboelastogram (TEG) versus ticagrelor for patients undergoing percutaneous coronary intervention (PCI). Methods Two hundred and sixty-three patients who had undergone PCI from August 2015 to August 2016 in Chinese PLA General Hospital were consecutively collected, and they were divided into clopidogrel group (n=123) and ticagrelor group (n=140). The antiplatelet effect of clopidogrel was detected by TEG. When high platelet reactivity HPR was defined as adenosine diphosphate (ADP) induced platelet inhibition rate≥50% was found in clopidogrel group, the maintenance dosage of clopidogrel was adjusted to 150 mg per day. All patients were followed-up for 12 months, and the incidence of MACE in two groups was compared. Results The incidences of stent thrombosis (ST), target vessel revascularization(TVR), angina pectoris recurrence (APAA) and cardiac death in two groups had no statistically significant difference (All P> 0.05).The incidences of readmission for chest pain and MACE in clopidogrel group were higher than those of ticagrelor group (4.9% vs 0.7%, P=0.042; 13.0% vs 5.0%, P=0.022). Conclusion The incidence of MACE in clopidogrel group is higher than that of ticagrelor group after PCI, which indicates the effect of tailored clopidogrel therapy is not superior to ticagrelor.