OBJECTIVE： To study the effects of rabeprazole （RPZ） on in vivo anti-platelet aggregation and metabolism of clopidogrel in rats. METHODS： Totally 40 SD rats were randomly divided into blank control group， RPZ group， CLP group， RPZ+CLP group and CLP+RPZ group， with 8 rats in each group. The dose of CLP and RPZ were 6.75 and 0.9 mg/kg， with medication interval of 2 h， for consecutive 14 d. The maximal platelet aggregation （MPA）， platelet reaction index （PRI）， gastric mucosal injury score and blood concentration [carboxylic acid of clopidogrel （CA） and active metabolite of clopidogrel （AM） were detected. The relationship of MPA and PRI with CA and AM were analyzed by Pearson relation analysis. RESULTS： Compared with blank control group， MPA and PRI of rats were decreased significantly in CLP group， RPZ+CLP group and CLP+RPZ group （P＜0.05）. Gastric mucosal injury score was increased significantly （P＜0.05）， while MPA， PRI and gastric mucosal injury score had no significant change in RPZ group （P＞0.05）. Compared with CLP group， MPA and PRI were increased significantly in RPZ+CLP group and CLP+RPZ group （P＜0.05）； gastric mucosal injury score was decreased significantly （P＜0.05） and blood concentration of AM was also decreased significantly （P＜0.05）. Blood concentration of CA in 3 groups had no significant change （P＞0.05）. MPA and PRI were both negatively related with AM （r＝－0.689， －0.765，P＜0.05）， while they had no significant correlation with CA （r＝－0.117， 0.048， P＞0.05）. CONCLUSIONS： RPZ can inhibit the antiplatelet effect of CLP and CLP-induced gastric mucosal injury， and medication order of two drugs doesn’t influence CLP metabolism.