Abstract: Objective: To observe the regulatory effect of compound Kushen injection on immune function, hematopoietic function and tumor markers in patients with breast cancer. Methods: A total of 231 cases of patients with breast cancer were divided into the observation group and the control group according to the random number table method, 121 and 110 cases in each group respectively. The control group was given routine chemotherapy,and the observation group was additionally treated with compound Kushen injection based on the treatment of the control group. The effect of enhancing white blood cell,the changes in immune function and hematopoietic function as well as the content of tumor markers and the incidence of adverse reactions in the two groups were compared. Results: The total effective rate was 95.04% in the observation group, higher than that of 75.45% in the control group, the difference being significant(P<0.05). After treatment,CD4+ and CD4+/CD8+ in the control group were increased when compared with those before treatment(P<0.05), NK was decreased(P<0.05);the CD3+,CD4+ and CD4+/CD8+ in the observation group were increased when compared with those before treatment(P<0.05), CD8 + was decreased(P<0.05). After treatment, CD4 + , CD4 +/CD8 + and NK in the observation group were higher than those in the control group(P<0.05). After treatment, the levels of white blood cell, hemoglobin and platelets in the control group were decreased when compared with those before treatment(P<0.05),and the level of white blood cell in the observation group was decreased(P<0.05). After treatment, the levels of white blood cell, hemoglobin and platelets in the observation group were higher than those in the control group(P<0.05). After treatment,the contents of carcinoembryonic antigen(CEA) and cancer antigen 153(CA153) in the two groups were decreased when compared with those before treatment,and the contents of CEA and CA153 in the observation group were lower than those in the control group,differences being significant(P<0.05). The incidences of nausea and vomiting,alopecia,neutropenia, thrombocytopenia and function injury of the liver and kidney in the observation group were all lower than those in the control group, differences being significant(P<0.05). Conclusion: Compound Kushen injection assisting chemotherapy can significantly enhance white blood cell, improve hemopoietic function of bone marrow, body immunity and chemotherapy tolerance, effectively reduce side effect of chemotherapeutic drugs and relieve clinical symptoms, so as to improve chemotherapeutic effect.