Objective To observe attenuation and synergy of postoperative chemotherapy combined with Tianzhicao capsule in patients who suffered from breast cancer. Methods 66 cases after radical mastectomy were randomly divided into treatment group 31 cases and 35 cases of control group. The patients of control group were treated with chemotherapies of CAF and TA. Treatment group patients were given Tianzhical capsule orally at the same time. Nausea and vomitting,the arrest of bone marrow before and after treatment were observed. The grade of life quality about every patient was evaluated. Results Myelosuppression and the occurrence of nausea and vomitting in treatment group was obviously lower than control group (P ＜ 0.05). The proportion of improvement and stabilization for the quality of life in treatment group was markedly higher than control group (P ＜ 0.05). Conclusion Traditional Chinese drug Tianzhicao capsule had attenuation and synergy to postoperative chemotherapy in breast cancer.