To study correlations between expression of microRNA-146a (miR-146a) and immunoglobulin and inflammatory cytokines in serum of patients with Guillain-Barr e syndrome (GBS). Methods: Eighty-four patients with GBS were selected as the experimental group and 50 healthy individuals as controls. Reverse transcription-PCR was used to detect expression of miR-146a in peripheral blood of all participants. Immunoturbidometric assay was used to detect immunoglobulins (Ig)G, IgA, and IgM in peripheral blood of all participants. The levels of interleukin-6 (IL-6), C-reactive protein (CRP), and tumor necrosis factor a (TNF-a) were measured by ELISA in peripheral blood. The expression of miR-146a was compared between the two groups and Pearson correlation analysis was used to analyze correlations between miR-146a and immunoglobulin and inflammatory factors. Results: Expression of miR-146a was higher in the GBS group than in controls. Expression of IL-6, CRP, TNF-a, and IgG was significantly higher in the GBS group than in controls. miR-146a was significantly and positively correlated with IL-6, CRP, TNF-a, and IgG but not with IgA and IgM. Conclusion: The expression profile of miR-146a in patients with GBS differs from that in healthy individuals. Thus, miR-146a may participate in the pathogenesis of GBS by regulating immune and inflammatory responses.