Objective To study the protective mechanism of Chinese medicine Suxiao Jiuxin Pills (& x901f;(sic)& x6551;(sic)& x4e38;, SXJ) on myocardial ischemia and reperfusion (I/R) injury. Methods Mouse myocardial I/R injury model was created by 30-min coronary artery occlusion followed by 24-h reperfusion, the mice were then divided into the sham group (n=7), the I/R group (n=13), the tirofiban group (TIR, positive drug treatment,n=9), and the SXJ group (n=11). Infarct size (IS), risk region (RR), and left ventricle (LV) were analyzed with double staining methods. In addition, H9C2 rat cardiomyocytes were cultured with Na(2)S(2)O(4)to simulate I/Rin vitro. The phosphorylation of extracellular regulated protein kinases1/2 (ERK1/2), protein kinase B (AKT), glycogen synthase kinase-3 beta (GSK3 beta), and protein expression of GATA4 in nucleus were detected with Western blot assay. Results The ratio of IS/RR in SXJ and TIR groups were lower than that in I/R group (SXJ, 22.4% +/- 6.6%; TIR, 20.8%+/- 3.3%; vs. I/R, 35.4%+/- 3.7%,P<0.05, respectively).In vitroexperiments showed that SXJ increased the Na2S2O4-enhanced phosphorylation of AKT/GSK3 beta and nuclear expression of GATA4. Conclusion SXJ prevents myocardial I/R injury in mice by activating AKT/GSK3 beta and GATA4 signaling pathways.