Abstract: Background and Objective: QingFengTeng (Sinomenii caulis) and GuiZhi (Cmnamomi mmulus) were used together in the treatment of rheumatoid arthritis (RA) with high frequency in China. However, there are few researches on the therapeutic effects of the combination of the two herbs on RA. The present study was to investigate the anti-RA activities of different combination of the two herbs on adjuvant induced arthritis (AA) rats and further explore its possible mechanism. Materials and Methods: Four herb extracts were prepared with 70% ethanol from different combination of the two herbs. The AA rats were induced by intradermal injection of complete Freund's adjuvant (CFA) in left hind foot pad of rat. Sinomenone hydrochloride tablets (Sin) was chosen as the positive drug. Paw swelling and histopathological changes were evaluated. The serum levels of interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-10 (IL-10) and tumor necrosis factor alpha (TNF-α) were detected. Results: The results showed all the ethanol extracts of the formula ameliorated AA symptoms. Extract (4:1) and extract (3:1) significantly decreased the paw swelling, greatly elevated the levels of IL-10, got better results in improving pathological changes and their efficacies were slightly superior to the other treatment groups. Conclusion: For the first time, the suppressive mechanism of a formula composed of QingFengTeng and GuiZhi on AA rats were studied. These results indicated that the herb formula may be a potential candidate for the treatment of RA.