Objective To explore the effects of Shenfu injection on cardiac function in patients with acute myocardial infarction. Methods 58 patients with acute myocardial infarction diagnosed in our hospital from March 2016 to March 2017 were selected and divided into two groups according to the random number table method. 29 cases given routine treatment were taken as routine group, and 29 cases treated with routine treatment + Shenfu injection were selected as study group. The efficacy of the two groups was observed. Results The total effective rate in study group was significantly higher than that in routine group (79.31% vs 51.72%) (P<0.05). After treatment, the indexes of CI, CO and LVEF in the two groups were higher than those before treatment while the index of HR was significantly lower than that before treatment (P<0.05). The improvements of cardiac function in study group were better than those in routine group (P<0.05). After treatment, the indexes of TNF-α and CPR in the two groups were lower than those before treatment while the index of NO was higher than that before treatment (P<0.05). The improvements of TNF-α, CPR and NO in study group were significantly better than those in routine group (P<0.05), and there were no obvious adverse reactions in the two groups. Conclusion Shenfu injection can effectively improve the cardiac function of patients with acute myocardial infarction and reduce the inflammatory responses, and its clinical treatment was safe and effective.