Objective: To study the effect of Shenmai injection on the efficacy and side effects of chemotherapy in acute leukemia. Methods: Sixty-two patients with acute leukemia admitted to the hospital between February 2018 and June 2019 were enrolled in this study. All patients were divided into observation and control groups according to different treatment methods in chemotherapy. The control group was treated with chemotherapy alone. The observation group was treated Shenmai injection combined with chemotherapy. The treatment effect of the two groups was compared, and the incidence of bone marrow blood and side effects before and after treatment were compared. Results: The therapeutic effect of the observation group was 93.55% which was much higher than that of the control group of 74.19%, P<0.05. The bone marrow blood levels of WBC, PLT and Hb in the observation group before and after treatment were 23.97±3.05, 6.76±1.27, 69.01±8.15, 66.96±9.46, 91.07±8.15, 89.35±7.46, respectively, compared with the control group. The difference in the situation after treatment was found to be significant. The incidence of toxic side effects such as nausea and vomiting, impaired liver function and renal dysfunction in the observation group was 9.68%, which was lower than that of the control group (32.26%, P<0.05). Conclusion: Shemai injection has significant effects on the efficacy and side effects of chemotherapy in acute leukemia and effectively improves the effect of chemotherapy.