Objectives : The object of this study was to verify the inhibitory effect of a decoction of Eucommiae ulmides OLIVER (EU) and Dipsacus asperoides C. Y. Cheng et T.M.Ai (DA) on Collagen II-induced Arthritis Mice (CIA mice). Methods : DBA/1OlaHsd mice were immunized with bovine type II collagen. Boostnig same collagen 21 days later, arthritis was induced and then administrated orally the extract of EU+DA (200 or 50 mg/kg) once a day for 4 weeks and compared with that of methotrexate (MTX, 0.3 mg/kg) as a positive control. Results : Administration of EU+DA suppressed the inflammatory progression of CIA mice and the results were 1. Arthritis index of CIA mice was decreased. 2. EU+DA decreased the production of TNF-$alpha$, IL-6, IL-$1{eta}$ in the serum of CIA mice. 3. EU+DA decreased the level of IgM. 4. EU+DAincreasaed $CD3^+$, $CD4^+$, $CD4^+$/CD25 but decreased $CD19^+$, $CD3^+/CD49b^+$(NKT), $CD3^-/CD49b^+$(NK), $B220^+/CD23^+$ in PBMC of CIA mice. 5. EU+DA decreased $CD3^+$, $CD4^+$, $CD3^+/CD69^+$ of paw joint in CIA mice. 6. EU+DA decreased subsynovial inflammation. Conclusions : This results demonstrated that extract of EU+DA suppressed the inflammatory progression of CIA mice and supported further studies are required to clarify a mechanism of therapeutic role.