Objective：To discuss the effect of tetrandrine on the myocardial infarction area and cardiac-function protein kinase B(Akt)/glycogen synthase kinase-3b(GSK-3b)signal pathw ay of rats with myocardial ischemia/reperfusion injury(I/R).Methods： 180 healthy m ale SD rats of SPF level were divided into the shamoperation group，the model group， the sim vastatin group and the groups of tetrandrine in low，middle and high doses randomly.14 days before the model establishment，the sim vastatin group was given sim vastatin in 2.0m g/(kg·d)by gavage；20 minutes before the model establishment，the groups of tetrandrine in low，middle and high doses were given tetrandrine in 1.5m g/kg，3.0m g/kg and 6.0m g/kg by intraperitoneal injection respectively；the shamoperation group and the model group were given saline of the same volume.Established the model of I/R rats by ligating the left anterior descending artery.After 24 hours of perfusion，measured the content of cardiac troponin T(cTnT)and the activity of creatine kinase isoenzyme(CK-MB)in serum and lactate dehydrogenase(LDH)； measured the myocardial infarction area by nitrotetrazolum blue chloride(NBT)staining； detected cardiac function via echocardiography；detected the protein expression of Akt，pAkt，GSK-3b and pGSK-3b via Western blot.Results：Comparing with the shamoperation group，the content of cTnT and the activity of CK-MB and LDH in serumof the model group were all significantly increased，the myocardial infarction area was significantly enlarged，left ventricular internaldiameter at diastole(LVIDd)and left ventricular internal diameter at systole(LVIDs)were both increased evidently，andthe ratios of pAkt/Akt and pGSK-3b/GSK-3b in myocardial tissue were evidently decreased，differences being significant( P ＜0.05).Comparing with the modelgroup，the content of cTnT and the activity of CK-MB and LDH in serumof the sim vastatin group and the groups of tetrandrine in middle and high doses were all significantly decreased，the myocardial infarction area was significantly reduced，LVIDd and LVIDs were both decreased evidently，and the ratios of pAkt/Akt and pGSK-3b/GSK-3b in myocardial tissue were evidently increased，which appeared dose-dependent，differences being significant( P ＜0.05).Conclusion： Tetrandrine can significantly alleviate the myocardial injury of I/R rats and improve cardiac function； its mechanism may be related to the activation of Akt/GSK-3b signalpathw ay.