Objective: To study the effect of Wenhua Juanbi Recipe(温化蠲痹方, WJR) on expression of receptor activator of nuclear factor kappa B ligand(RANKL), osteoprotegerin(OPG), and tumor necrosis factor receptor superfamily member 14(TNFRSF14, also known as LIGHT) in rats with collagen-induced arthritis(CIA). Methods: CIA rats were generated by subcutaneous injection of bovine collagen type-Ⅱ at the tail base. Sixty CIA rats were randomly assigned(10 animals/group) to: model, methotrexate(MTX)-treated(0.78 mg/kg body weight), and WJR-treated(22.9 g/kg) groups. Healthy normal rats(n=10) were used as the normal control. Treatments or saline were administered once daily by oral gavage. Rats were sacrificed at day 28 post-treatment and knee synovium and peripheral blood serum were collected. Toe swelling degree and expression of RANKL, OPG, and LIGHT were determined by Western blot and immunohistochemistry. Results: Compared with the normal group, toe swelling degree was significantly increased in the model group(P<0.01). After treatment, toe swelling degree decreased significantly in the WJR and MTX groups compared with the model group(P<0.01). Compared with the normal group, expression of RANKL and LIGHT were significantly increased and OPG significantly decreased in peripheral blood and synovium of the model group(P<0.01). Conversely, RANKL and LIGHT expression were significantly reduced and OPG increased in the WJR and MTX groups compared with the model group(P<0.01). No statistically significant difference existed between WJR and MTX groups. Conclusion: WJR likely acts by reducing RANKL expression and increasing OPG expression, thus inhibiting RANKL/RANK interaction and reducing LIGHT expression, thereby inhibiting osteoclast formation/activation to block bone erosion. Objective: To study the effect of Wenhua Juanbi Recipe on expression of receptor activator of nuclear factor kappa B ligand (RANKL), osteoprotegerin (OPG), and tumor necrosis factor receptor superfamily member 14 (TNFRSF14, Methods: CIA rats were generated by subcutaneous injection of bovine collagen type-II at the tail base. Sixty CIA rats were randomly assigned (10 animals / group) to: Treatments or saline were administered once (n = 10) were used as the normal control. model, methotrexate (MTX) -treated (0.78 mg / kg body weight), and WJR-treated (22.9 g / daily by oral gavage. Rats were sacrificed at day 28 post-treatment and knee synovium and peripheral blood serum were collected. Toe swelling degree and expression of RANKL, OPG, and LIGHT were determined by Western blot and immunohistochemistry. Results: Compared with the normal group, toe swelling degree was significantly inc Compared with the normal group, expression of RANKL and LIGHT were significantly increased (P <0.01). and OPG significantly decreased in peripheral blood and synovium of the model group (P <0.01). Conversely, RANKL and LIGHT expression were significantly reduced and OPG increased in the WJR and MTX groups compared with the model group Significant difference existed between WJR and MTX groups. Conclusion: WJR likely acts by reducing RANKL expression and increasing OPG expression, thus inhibiting RANKL / RANK interaction and reducing LIGHT expression, thereby inhibiting osteoclast formation / activation to block bone erosion.