Arjuna (Terminalia arjuna) is a medicinal plant used in many polyherbal hepatoprotective formulations. Although widely claimed to be antioxidant, data supporting such actions of Arjuna are limited. Cells incubated with TBHP showed the significant induction of OS response in cytosol manifested as lipid hydroperoxide (76%-198%) and the generation of reactive oxygen species (60%-127%). cells treated with AETA (100 µg/ml) along with TBHP offered significant protection by reducing levels of lipid hydroperoxide (33%-62%) and ROS (69%) and by increasing antioxidant capacity (54%-81%) and levels of reduced glutathione (49%-82%). Further, it also enhanced the activities of endogenous antioxidant enzymes (superoxide dismutase, 60%; catalase, 35%-82%; glutathione peroxidase, 42-65 %; glutathione reductase, 48%-62%; and glutathione S-transferase, 22%-100%). Taken together, these data suggest that Arjuna can protect against the oxidative damage induced by TBHP and may be effectively used as a hepatoprotective adjuvant to abrogate OS in vivo.