The purpose of this study is to examine the effect of Vigna angularis ethanol extract (VA-E) on papain induced arthritis in C57BL/10 mice. The C57BL/10 mice were injected with papain and oral administration of Vigna angularis ethanol extract (VA-E) at different doses (100 and 200 mg/kg) once a day for 42 days and compared with untreated mice. Histological examination and the measurement of inflammatory cytokine release were performed. The results showed that comparing with untreated mice, the treatment with Vigna angularis ethanol extract (VA-E) decreased the pathological changes of knee joint tissue. The level of inflammatory cytokine secreted from the tissues, such as IL-$1{eta}$ (interleukin-$1{eta}$), IL-6 (interleukin-6), TNF-${alpha}$ (Tumor Necrosis Factor-${alpha}$), were decreased. These results were confirmed by the quantification of cartilage volume using micro CT scanning. Consequently, Vigna angularis ethanol extract (VA-E) has a therapeutic potential in inflammatory joint diseases such as osteoarthritis.