Objective:To investigate the expression of change of Th17 cells and related cytokines in multiple sclerosis patients and its clinical significance. Methods:Totally 27 multiple sclerosis patients(MS group) and 20 healthy subjects(control group) were selected. RT-PCR was used to detect IL-17 mRNA;ELISA was used to detect IL-17,IL-23 and IL-6;FACS was used to detect Th17 cells in peripheral blood. Results:Level of IL-17 mRNA was significantly increased in MS group(P<0.05). When compared with that control group,expression of Th17 cells and related cytokines(IL-17,IL-23 and IL-6) was significantly increased in MS group(P<0.05). Conclusion:Th17 cells and related cytokines may participate in the pathogenesis of multiple sclerosis. Detection of Th17 cells could have clinical value in diagnosis of multiple sclerosis.