Aim Through simulating the ischemia/reperfusion of cardiomyocytes in vivo by constructing a model of cardiomyocyte hypoxia and reoxygenation in vitro, to verify the effect of Aliskiren on improving the myocardial ischemia/reperfusion injury and to explore its mechanism in regulating apoptosis. Methods Cell experiments were divided into four groups:normal oxygen supply group (Control), hypoxia/reoxygenation group (H/R), Aliskiren+H/R group, NF-κB P65 specific inhibitor (bay11-7082)+H/R group. CCK-8 was used to detect the survival rate of cardiomyocytes pretreated with different concentrations of Aliskiren, and ELISA was performed to determine the levels of inflammatory factors (TNF-α, IL-6) in each experimental group. Hoechst33258 staining and Annexin V/PI dual staining flow cytometry were conducted to evaluate the myocardial cell apoptosis ratio in each group. The JC-1 kit was used to measure mitochondrial membrane potential and cardiomyocyte ATP content. Meanwhile, the Caspase-3 activity kit was performed to detect the activity of apoptotic proteases in each group. Results When the concentration of Aliskiren was less than 20 mmol/L, a positive correlation with cardiomyocyte activity was showed, and when between 40 mmol/L and 80 mmol/L, there was a negative correlation. The optimal concentration of Aliskiren was 20 mmol/L at which the myocardial cell activity is the highest. Compared with the H/R group, Aliskiren can decrease the expression of TNF-α and IL-6 ((129.33±5.86) ng/L vs (319.00±4.58) ng/L, P＜0.05; (29.67±1.53) ng/L vs (64.67±2.08) ng/L, P＜0.05), and significantly reduce the apoptosis rate of cardiomyocytes ((7.23%±1.14%) vs (32.25%±3.15%), P＜0.05), and reduced the proportion of cardiomyocytes with energy disorders ((6.9%±1.6%) vs (13.5%±1.7%), P＜0.05), what’s more, Aliskiren can gain the function of stabilizing mitochondrial membrane potential ((3.90±0.60) vs (1.80±0.16), P＜0.05) and inhibit the activity of apoptotic protease Caspase-3 ((2.26±0.35) vs (3.26±0.62), P＜0.05). It is of great importance that there was no statistical difference in the experimental results between Aliskiren+H/R group and bay11-7082+H/R group.Conclusion Aliskiren can improve myocardial ischemia/reperfusion injury by inhibiting inflammatory response and regulating mitochondrial receptor-mediated apoptosis. Based on the experimental results, it can be speculated that the role of Aliskiren in regulating apoptosis may be related to inhibition of NF-κB expression.