Abstract： Objective： To observe the clinical effect of Fuzheng Jiedu Decoction combined with intensity modulated and conformal radiation therapy for post-operative breast cancer. Methods：A total of 80 cases of patients with post- operative breast cancer were selected as the study subjects，and divided into the control group and the observation group according to the random number table method ， with 40 cases in each group. The control group was treated with routine intensity modulated and conformal radiation therapy，and the observation group was additionally treated with Fuzheng Jiedu Decoction based on the treatment of the control group. The adverse reactions of medication were compared between the two groups. Before and after treatment，the immune function and quality of life were compared between the two groups. Results： The total incidence of adverse reactions of medication was 17.5% in the observation group，lower than that of 55.0% in the control group (P＜0.05). Before treatment，there was no significant difference being found in the comparison of levels of red blood cell count，white blood cell count，lymphocyte count，and monocyte count between the two groups (P＞0.05)；after treatment，the above levels in the two groups were decreased (P＜0.05)， and the levels in the observation group were higher than those in the control group (P＜0.05). Before treatment， there was no significant difference being found in the comparison of levels of immunoglobulin G (IgG)， immunoglobulin A (IgA)， and immunoglobulin M (IgM) between the two groups (P＞0.05)；after treatment，the levels of IgG，IgA and IgM in the two groups were decreased (P＜0.05)，and the levels in the observation group were higher than those in the control group (P＜0.05). Before treatment，there was no significant difference being found in the comparison of levels of CD3+，CD4+，CD8+ and CD4+/CD8+ between the two groups (P＞0.05)；after treatment，the levels of CD3 +，CD4 + and CD4 +/CD8 + in the two groups were decreased (P＜0.05)，and CD8 + was increased (P＜0.05)；the levels of CD3 +，CD4 + and CD4 +/CD8 + in the observation group were higher than those in the control group (P＜0.05)，and CD8 + was lower than that in the control group (P＜ 0.05). Before treatment，there was no significant difference being found in the comparison of each single score and the total scores of Version 4 of Functional Assessment of Cancer Therapy - Breast (FACT-B4.0) between the two groups (P＞0.05)；after treatment，the each single score and total scores of FACT-B 4.0 in the two groups were increased (P＜0.05)， and the scores in the observation group were higher than those in the control group (P＜0.05). Conclusion： Fuzheng Jiedu Decoction combined with intensity modulated and conformal radiation therapy for patients with post- operative breast cancer can effectively reduce adverse reactions of postoperative medication，relieve immune injury induced by radiation therapy， and improve postoperative quality of life.