Objective To explore the intervention mechanism of myocardial ischemia/reperfusion injury (MI/IR) rats model from PI3K/AKT signaling pathway by preventive administration of polyphyllin I. Methods A total of 72 purchased clean-grade (SPF) SD rats were randomly divided into sham operation, model, aspirin, Polyphyllin I low-dose, medium-dose and high-dose groups(n=12), and the corresponding drug intervention was given for 2 weeks immediately after grouping, and the MI/IR model was constructed after 2 weeks of administration. After 24 h of successful model construction, cardiac function was first measured by color Doppler ultrasonography, then the rats were executed and the relevant tissues were collected by HE staining to observe myocardial pathology. TTC method was to detect myocardial infarction area. The kits were used to detect cardiac function indicators lactate dehydrogenase (LDH), creatine kinase isoenzyme MB (CK-MB) and glutathione transaminase (AST), antioxidant indicators malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione (GSH). The expression of myocardial phosphatidylinositol-3-kinase (PI3K), protein kinase B (AKT), B-cell lymphoma/factor 2 (Bcl-2) and Bcl-2-associated protein (Bax) were measured by Western blotting. Results The sham-operated group had neatly arranged myocardial fibers without edema, and the model group had myocardial fiber breaks. Myocardial fiber breakage was significantly improved in the three treatment groups of polyphyllin I and aspirin. Compared with sham operation group, the myocardial infarction area, LVEDP, LDH, CK-MB, AST and MDA were significantly increased in model group (P＜0.05), while LVDP, +dp/dtmax, -dp/dtmax, SOD and GSH were significantly decreased in model group (P＜0.05). Compared with model group, after aspirin and Polyphyllin I intervention, the myocardial infarction area, LVEDP, LDH, CK-MB, AST and MDA were significantly decreased (P＜0.05), while LVDP, +dp/dtmax, -dp/dtmax, SOD and GSH were significantly increased (P＜0.05). Tunnel staining showed that there was almost no myocardial apoptosis in the sham group, while in the model group showed a significant amount of apoptosis. Compared with the model group, the apoptosis was significantly improved in the aspirin group and the three Polyphyllin I groups. In addition, compared with sham operation group, the protein expressions of PI3K, Akt and Bcl-2 in model group were significantly decreased (P＜0.05), while Bax was significantly increased (P＜0.05). Compared with model group, the protein expressions of PI3K, Akt and Bcl-2 in the three dose Polyphyllin I groups and aspirin group were significantly increased (P＜0.05), while the Bax protein expression was significantly decreased (P＜0.05).Conclusion Polyphyllin I has a certain preventive effect on myocardial ischemia-reperfusion injury, and its mechanism may be related to its regulation of PI3K/AKT signaling pathway