Objective:To explore the generation of mature dendritic cells(DCs) induced from human peripheral blood monocytes in vitro. Methods:Monocytes were isolated from normal human peripheral blood mononuclear cells(PBMCs)and were separated into five groups after cultured with GM-CSF and IL-4 5 days later. The control group were added only GM-CSF and IL-4. One group were added polyriboinosinic polyribocytidylic acid[Poly(I:C)], one group were added calcium ionophore(CI),one group were added Poly(I:C) and CI, and the other group were added TNF-α. The morphology of cells was observed by microscope. The surface antigens of the induced cells were analyzed by fluorescence-activated cell sorting(FACS). T cell proliferating activity was determined by allo-MLR(mixed lymphocyte reaction) in vitro. Results:Large amount of mature DCs could be obtained from monocytes by culture in presence of GM-CSF,IL-4,Poly(I:C) and CI. DC expressed high level of CD83, CD80, CD86 and CD40, and were potent to stimulate the proliferation of allo-lymphocytes. Conclusion:The phenotypes and functions of DC generated from PBMC by the treatment of cytokine combination can be improved by calcium ionophore and Poly(I:C).