Rheumatoid arthritis is the most common arthritis and is mainly characterized by symmetric polyarticular joint disorders. Eleutheroside E (EE), a principal active constituent of Acanthopanax senticosus, is reported to have anti-inflammatory effect by inhibiting NF-κB activities. However, the effects of EE on rheumatoid arthritis (RA) severity are largely unknown. The purpose of this study was to indicate whether EE could ameliorate arthritis and reduce inflammatory cytokine release in collagen-induced arthritis (CIA) mice. The results showed that EE attenuated the severity of arthritis by reducing the mean arthritis score and arthritis incidence. EE also significantly decreased the inflammatory cell infiltration, pannus formation, cartilage damage, and bone erosion of CIA mice. Furthermore, EE caused a marked decrease of the production of TNF-α and IL-6 in vivo and in vitro. These observations identify a novel function of EE that results in inhibition of cytokine release, highlighting EE was a potential therapeutic agent for RA.