Objective,2,To study the mechanism of action of Jinteng Qingbi Granules in the treatment of rheumatoid arthritis in model rats.,Methods,2,10 rats were randomly selected as the blank control group（A），and another 60 rats were used to establish RA model by collagen-induced arthritis.Fourteen days after modeling，the model rats with arthritis index（AI）score≥4 were randomly divided into model control group（B），low（C），middle（D）and high dose（E）groups of Jinteng Qingbi Granules，methotrexate group（F）and tripterygium wilfordii polyglycoside group（G），with 6 rats in each group.Group C，D and E were respectively given 1.05，2.1 and 4.2 g/kg Jinteng Qingbi Granules by intragastric administration，three times a day.Group F was given methotrexate 0.8 mg/kg by gavage every 4 days； group g was given 2.625 mg/kg tripterygium wilfordii polyglycoside by gavage three times a day.Group A and group B were given equal volume of 0.9% sodium chloride injection.All groups were given intragastric administration for 4 weeks.The joint index （AI） scores of each group were compared. The anti-inflammatory factor interleukin （IL）⁃10， transforming growth factor β1（TGF⁃β,1,），IL⁃1β，tumor necrosis factor⁃α（TNF⁃α）and IL⁃17 in peripheral blood were detected by ELISA.Immunohistochemistry was used to detect the expression of osteoprotegerin（OPG）/nuclear factor κB receptor activator ligand（RANKL）and CD34，and Microvessel density（MVD）count.,Results,2,Compared with group A，the levels of IL⁃10 and TGF⁃β,1, in peripheral blood of rats in group B were decreased，but the levels of IL⁃1β， TNF⁃α and IL⁃17 increased（,P,<,0.05）.The expressions of OPG，RANKL and MVD in synovium of knee joint were increased（,P,<,0.05）.The joint swelling in group C，D，E，F and G was lighter than that in group B（,P,<,0.05）.In group C，D，E，F and G，the levels of IL⁃10，TGF⁃β,1, and TNF⁃α in peripheral blood were increased，while the levels of IL⁃1β and IL⁃17 decreased（,P,<,0.05）.The expressions of RANKL and MVD in synovium of knee joint of rats in groups D，E，F and G were decreased（,P,<,0.05），while the expression of OPG in synovium of knee joint of rats in groups C，D，E，F and G increased（,P,<,0.05）.,Conclusion,2,Jinteng Qingbi Granules can affect the development of RA by inhibiting inflammatory response， angiogenesis， and OPG/RANKL expression ratio.