to study the effect of human bone marrow derived mesenchymal stem cells (hMSCs) on cytokines secretion (IFN-γ, TNF-α, IL-10, IL-6, IL-4 and IL-2) of allogeneic DC-CIK cells (in co-culture of CIK cells with DC), which investigate the mechanism of immunoregulation induced by hMSCs. the hMSCs from bone marrow were isolated, expanded and identified by cell morphology, differentiation into neuron-like cells with NSE, fat-like cells with red-oil stain, and expression of CD29, CD44. The DC and CIK cells from peripheral blood were isolated, expanded and identified by CD1α, HLA-DR or CD3(+);CD56(+);. The hMSCs were co-cultured with DC-CIK cells according to ratio 1:10. The expression of the six cytokines in supernatant was evaluated by flow cytometry after 4 days of DC-activated CIK cells in co-culture with hMSCs. the hMSCs displayed a fibroblast-like morphology and the positive cells of CD29 and CD44 were 96.6%, 94.6%, which have the capacity of differentiation into neuron-like cells with expressed NSE as well as fat-like cells with red-oil stain positive. The expression of CD1α, HLA-DR in DC was (91.9 ± 10.04)% and (88.8 ± 8.92)%. The CD3(+);CD56(+); double positive cells in DC-CIK cells was (29.23 ± 12.23)% compared to CIK cells with (15.98 ± 2.49)%. The cytokines secretion of DC-CIK cells in co-culture with hMSCs was IFN-γ (135.05 ± 48.19) ng/L; TNF-α (11.33 ± 1.42) ng/L; IL-10 (10.15 ± 2.25) ng/L; IL-6 (494.63 ± 235.222) ng/L; IL-4 (7.07 ± 2.30) ng/L and IL-2 (1074.6 3 ± 303.74) ng/L. In control group (DC-CIK cells) the secretion of IFN-γ, TNF-α, IL-10, IL-6, IL-4 and IL-2 was (717.6 ± 248.15) ng/L; (17.78 ± 7.52) ng/L; (29.95 ± 12.76) ng/L; (8.03 ± 0.21) ng/L, (9.08 ± 3.07) ng/L as well as IL-2 1 250 ng/L. the secretion of IFN-γ and IL-10 were down-regulated. It probably implied that hMSCs had the effect of immunoregulation on DC-CIK cells.