Abstract: OBJECTIVE To observe the effects of Tripterygium Glycosides tablets on the expression of colon mucosa of LPS/TLR4 signaling pathway in mice with ulcerative colitis(UC) induced by dextran sulphate sodium(DSS), and to explore its possible mechanisms. METHODS BALB/c mice were randomly divided into 6 groups: model control group, low, middle and high dose of Tripterygium Glycosides tablets group, negative control group and normal control group. DSS was used to establish mice model of UC. Suspension of Tripterygium Glycosides tablets was administrated for 21 d. RT-PCR was adopted to detect the expression of TLR4 mRNA and protein. Western blotting was used to determine the phosphorylation level of NF-κB p65. Colon tissue frozen sections were stained by double immunofluorescence staining, and confocal laser confocal microscope was used to observe the expression and distribution of NF-κB. RESULTS The expression level of TLR4 of 3 groups of tripterygium glycosides was significantly decreased(P<0.01). Compared with normal control group, the expression level of TLR4 of middle and high dose of tripterygium glycosides and negative control group had no significant difference. Compared with model control group, the phosphorylation level of NF-κB p65 of low dose group decreased slighely,and decreased obviously in middle and high dose group, but there was no statistic difference(P>0.05). CONCLUSION The tripterygium glycosides tablets can inhibit the expression LPS/TLR4 signaling pathway and the inflammatory reaction in UC mice, and it had a certain protective effect on the pathogenesis of UC.