Cynodon dactylon (L.) (Poaceae) is traditionally used herb to treat fevers, skin diseases and rheumatic affections. The ethanolic extract of C. dactylon was found to be safe at all the dose levels (100, 200 and 400 mg/kg, orally) and there was no mortality up to the dose of 5000 mg/kg of extract when administered orally. C. dactylon showed significant antiarthritic activity against Freund's complete adjuvant induced arthritis in rats. Treatment with C. dactylon significantly reduced the mean percentage change in injected and non injected paw, ankle diameter, clinical severity and significantly increased body weight. Results were confirmed using biochemical parameters; there was a significant improvement in the levels of Hb and RBC in C. dactylon treated rats. The increased levels of WBC, ESR, C- reactive protein (CRP) and TNFalpha were significantly suppressed in C. dactylon treated rats. C. dactylon showed protective effect in arthritic joints but it has been supported by an improvement in bone lesions rather than in cartilage lesions. It can be concluded that ethanolic extract of C. dactylon at a dose of 400 mg/kg is effective in improving haematological level, CRP and reducing TNFalpha level. Phytochemical screening showed the presence of alkaloids, flavonoids and glycosides in ethanolic extract. All the above results support the traditional uses of the plant in the treatment of rheumatoid arthritis.