Abstract: Objective： To investigate the difference in efficacy of oral aspirin， clopidogrel and combined anti-platelet aggregation therapy in acute cerebral infarction patients， and analyze the cause， so as to provide the theoretical reference for clinical practice. Methods： The 208 hospitalized patients with acute cerebral infarction were divided into group A (aspirin group) 53 cases， group B (clopidogrel group) 59 cases and group C (combination group) 96 cases. The platelet inhibition rate was measured in all patients， and the patients’ general information were collected and analyzed. Results： The usage of PPI drugs in group B and group C was higher than group A (P<0.05). The comparison of platelet inhibition rate among three groups showed that the platelet inhibition rate induced by AA pathway were higher than that induced by ADP pathway (P<0.05), but there was no statistical difference in platelet inhibition rate induced by AA or ADP pathway between sigle drug group and combination group(P＞0.05). The effective rate of platelet inhibition in group C was higher than that in group A and B(P<0.05). Conclusion： The clinical resistance rate of clopidogrel is more common than that of aspirin. Attention should be paid to the metabolic genotype of clopidogrel. The understanding of the pharmacokinetics of clopidogrel and the drug interaction should be improved. Combined antiplatelet therapy can improve antiplatelet aggregation through AA and ADP pathway, but there is no synergistic effect.