Objectives: Oral cancer is the fifth most frequent cancer worldwide and India has recorded the highest incidence (40-50%) of oral malignancy. This study is designed to investigate the effect of aqueous extract of Terminalia arjuna bark (TaBet) on circulatory lipid peroxidation and antioxidant status during 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch carcinogenesis.Methods: Male Syrian golden hamsters painted with 0.5% 7,12-dimethylbenz[a]anthracene on the buccal pouches and developed oral squamous cell carcinoma were included in this study.Results: The enhanced Thiobarbituric acid reactive substances in circulation of tumor-bearing animals was accompanied by a significant decrease in the levels of vitamin C, vitamin E, reduced glutathione, superoxide dismutase, catalase and glutathione peroxidase. Administration of TaBet (500 mg/kg body weight) significantly suppressed DMBA-induced hamster buccal pouch carcinomas, decreased lipid peroxidation and enhanced the levels of antioxidants. Conclusion: The chemopreventive potential of TaBet is probably due to its antilipidperoxidative effect or the presence of some potent bioactive chemopreventive principles in the bark of Terminalia arjuna. The results of the present study indicate that T. arjuna may emerge as a putative chemopreventive agent against oral carcinogenesis.