To study the therapeutic effects of chrysin on MI/RI rats，and to observe the proteins expression of Bax and Bcl-2.Methods:According to weight，A total of 60 SD rats after adaptive feeding for 2 weeks were divided into a sham operation group，a model group，a positive drug ramipril group，chrysin low，medium and high dose groups，n=10.The course of treatment was 2 weeks.Later，the MI/RI model was established by reversible left anterior descending coronary artery ligation.The sham operation group only threaded but not ligated.Later，the MI/RI model was established by reversible left anterior descending coronary artery ligation.The sham operation group only threaded but not ligated.After the operation，blood was collected for serum creatine kinase isoenzyme(CK-MB)，lactate dehydrogenase(LDH)，interleukin(IL)-6，superoxide dismutase(SOD)and malondialdehyde(MDA)content.TTC method was used to evaluate myocardial infarction area，HE staining was used to observe myocardial pathology.Western Blot was used to detect myocardial Bax and Bcl-2 protein expression characteristics.Results:Compared with the sham group，the infarct size in the model group was increased(P<0.05)，the myocardial fibers were broken，compared with the model group，the myocardial infarct size was improved in the 3 dose groups of Chrysin and Ramipril group(P<0.05).Cardiomyocyte morphology improved; compared with the sham group，serum CK-MB，LDH，IL-6 and MDA increased in the model group(P<0.05)，SOD decreased(P<0.05).Compared with the model group，CK-MB，LDH，IL-6 and MDA in the 3 doses of chrysin and ramipril group decreased(P<0.05)，and SOD decreased(P<0.05); Compared with the sham operation group，the expression of Bax protein in the myocardium of the model group was significantly increased(P<0.05)，and the expression of Bcl-2 was decreased(P<0.05).Compared with the model group，the three-dose group of chrysin and expression Bax protein in Puri group was reduced(P<0.05)，and Bcl-2 was up-regulated(P<0.05).Conclusion:Chrysin has a regulatory effect on serum myocardial enzymes CK-MB and LDH，inflammatory factor IL-6，oxidation and antioxidant indicators MDA and SOD in MI/RI rats，and can reduce the area of myocardial infarction.Its mechanism of action may be related to that of chrysin regulating Bcl-2 and Bax protein expression.