Objective To investigate new type cytokine induced killer cells expansion using advanced breast cancer′s peripheral blood .Methods peripheral blood mononuclear cells were isolated from 8 advanced breast cancer volunteers and co -cultured with Cytokine induced killer cells .These cells were placed in plastic flasks containing CIK-MediumTM supplemented with 10% auto-plasma in the presence of IL -2 ( 1 000 IU/mL) .The cultures were fed with CIK-MediumTM supplemented with IL -2 following the proliferation capacity . Cell proliferation was measured by cell counting during the cultivation .Fourteen days after cultivation ,cell mark-ers CD3/CD16/CD56 were examined by flow cytometry .51Cr and MTT assays were employed in cytotoxicity as-says.Cytokines were assayed by ELISA method .Results CD16+,CD16+CD56+,CD56+CIK cells were 5.8~11.6%in 2 ×107 fresh PBMCs and 95.2~97.6%in co-cultured cells after 18 days cultivation .The in vitro ex-pansion rate of new type cytokine induced killer cells was up to more than 8.2 ×108 in total,the cytotoxicity are ef-fective killing cells against MCF 7 and BT20 breast cancer cell lines .New type cytokine induced killer cells expand-ed from all PBMCs and secreted cytokines IFN -and TNF-.Conclusion The present culture could be useful to clarify the mechanisms of CIK cells expansion in vitro and feasible for breast cancer immmuno cell therapy .