Rat collagen II – induced arthritis is a model of chronic inflammation induced by Mycobacterium butyricum and collagen II. It is characterized by similar pathophysiological and pathobiochemical changes as rheumatoid arthritis (RA) in humans. In the present study, the biochemical and histopathological effects of vitamin E, allopurinol (Allo), on RA of rats were investigated. The oxidative stress indices and prostaglandin E were evaluated.