OBJECTIVE：To stu dy the improvement effects o f Trillium tschonos kii total sapo nins（TTM）on adjuvant-induced arthritis model rats and its mechanism. METHODS ：SD rats were randomly divided into model group （n＝44）and blank group （n＝6）. Model group was given Complete Freund ’s adjuvant to induce the adjuvant-induced arthritis model ；blank group was given constant volume of normal saline with same method. Model group were divided into model group ，Tripterygium wilfordii polyglycoside tablets group （40 mg/kg），TTM low-dose ，medium-dose and high-dose groups （50，100，200 mg/kg），with 6 rats in each group. Administration groups were given relevant medicine intragastrically ；blank group and model group were given normal saline intragastrically ，once a day ，for consecutive 9 days. After last intragastric administration ，the body weight and foot swelling degree （bilateral）were detected ，and arthritis score was performed. The contents of tumor necrosis fator α（TNF-α）， interleukin 1β（IL-1β）and IL- 6 were detected ；the pathomorphological changes of rat ankle were observed ；protein expression of NOD-like receptor protein 3 （NLRP3），apoptosis associated spot-like protein （ASC），caspase-1 were detected ；the protein expression of NLRP 3 in synovial tissue of ankle joint were also determined. RESULTS ：Compared with blank group ，foot swelling degree，serum contents of TNF-α，IL-1β and IL-6，the protein expression of NLRP 3，ASC and caspase- 1 in knee tissue as well as the protein expression of NLRP 3 in synovial tissue of ankle joint were increased significantly in model group （P＜0.05 or P＜ 0.01），while the body weight was decreased significantly （P＜0.05）. The obvious proliferation of synovial cells ，the congestion and inflammatory cell infiltration of synovial tissue were all observed. Compared with model group ，most of the above indexes were all reversed significantly in TTM groups （P＜0.05 or P＜0.01）；the pathological changes such as synovial cell proliferation ， congestion of synovial tissue and chondrocyte destruction were all relieved ，and inflammatory cell infiltration was alleviated.CONCLUSIONS：TTM can improve rheumatoid arthritis of rats， the mechanism of which may be associated with 用。E-mail：yulingling@ctgu.edu.cn inhibiting the activity of NLRP 3/caspase-1 signaling pathway and decreasing the expression of inflammatory factors TNF-α，IL-1β，IL-6.