This study aimed to analyze the clinical effects of dendritic cell (DC) and cytokine-induced killer (CIK) immunotherapy combined with chemotherapy on patients with metastatic breast cancer. Twenty patients were included into this study who were diagnosed as metastatic breast cancer (MBC). DC and CIK were augmented by in vitro culture and then rein fused into body through vein.The pain relief rate (RR), toxic and side effects of chemotherapy, immunity functions and living quality of patients were observed. DC and CIK cells were induced by the autologous peripheral blood mononuclear cells (PBMC). Meanwhile, flow cytometry was used to measure T cell subsets and natural killer T (NKT) cells in patients in the two groups before and after the biological treatment. After DC and CIK were rein fused into the patients body, no severe side-effect was found. It was also found that cellular immunotherapy combined with chemotherapy the immunotherapy of cells improved the immunity, the living quality of patients and the disease control rate (DCR). In conclusion, cellular immunotherapy produces small side effects; it combined with chemotherapyis able to improve the DCR and living quality of patients and prolong their lives.