Background: Immune-mediated inflammatory injury among systemic lupus erythematosus (SLE) individuals may be involved by dendritic cells (DCs) abnormality though the underlying mechanism remains incompletely understood. Objective: This study aimed to elaborate MSCs' potential in suppressing abnormal DCs cell function on peripheral blood mononuclear cells (PBMCs) among SLE patients. Methods: MSCs were isolated from human umbilical cord blood. On the other side, human PBMCs were isolated from 20 active SLE patients and 5 healthy controls. The PBMCs of SLE patients were divided into 5 groups: sham (Sh) and control (C) groups were treated with standard medium, and the treatment groups (T1, T2 and T3) was co-cultured with hUC-MSC at doses of 1:1, 1:25, and 1:50 (MSCs:PBMCs). The expression of CD11c in DCs was analyzed using flow cytometry, while the level of TNF-α, IFN-γ, IL-6 and IL-10 was analyzed using cytometric bead array (CBA). Results: The MSCs significantly downregulates CD11c of dendritic cells in all treatment groups. MSCs also significantly suppress the level of TNF-α, IFN-γ, IL-6 and the significantly enhance IL-10 level in all treatment groups. Conclusion: Therefore, MSCs could suppress DCs through regulating the proinflammatory milieu in PBMCs of SLE patients.Keywords: Autoimmune disease; Dendritic Cells; MSC; SLE.