〔Abstract〕 Objective To investigate the effects of resveratrol(Res) on fibroblast-like synoviocytes(FLS) in patients with rheumatoid arthritis(RA), and to explore the possible mechanism of Res inhibiting the release of inflammatory factors from FLS. Methods FLS from RA patients were culturedin vitroand treated with different concentrations of Res(0, 20, 40, 80, 160, 320 μmol/L). The viability of FLS cells was detected by CCK-8 assay after 12 and 24 h. The contents of inflammatory factor interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α) in cell supernatant were detected by ELISA. The expression levels of cyclic guanosine monophosphate-adenosine monophosphate synthase(cGAS) and stimulator of interferon gene(STING) were measured by Western blot; After lentivirus infection with FLS caused the cells to overexpress cGAS, the cells were divided into Control group(blank control), cGAS group(cGAS overexpression), Res+cGAS group(Res 160 μmol/L+cGAS overexpression) and Res group(Res 160 μmol/L). The expression level of STING protein in cells of each group was determined by Western blot, the viability of FLS cells in each group was detected by CCK-8, and the contents of inflammatory factor IL-6 and TNF-α in the supernatant of cells of each group were detected by ELISA method. Results The results of CCK-8 experiment showed that under 40, 80, 160 μmol/L Res treatment, FLS viability decreased significantly after 24 h compared with blank control group(P<0.01). ELISA results showed that the contents of IL-6 and TNF-α in cell supernatant were also significantly decreased after treatment with Res of 40, 80 and 160 μmol/L(P<0.01). Meanwhile, Western blot results showed that Res could significantly decrease the protein expression levels of STING and cGAS in FLS cells after treatment of 40, 80 and 160 μmol/L(P<0.05,P<0.01). Compared with the Control group, the expression level of STING protein in FLS increased after overexpression of cGAS(P<0.05); compared with the Res group, the content of inflammatory factors in the supernatant of FLS and the expression level of STING protein in FLS significantly increased after overexpression of cGAS(P<0.01,P<0.05). Conclusion The appropriate concentration of Res can inhibit the release of inflammatory cytokines in FLS cells, which may be related to the blocking of cGAS-STING signaling pathway.