Background and Aims. Despite it being a highly potent antineoplastic drug, cisplatin has important toxic adverse effects limiting its use such as nephrotoxicity, neurotoxicity and ototoxicity. It is thought that cisplatin-induced hepatotoxicity is caused by oxidative stress resulting from increased reactive oxygen species (ROS). Apocynin (APO) exerts its antioxidant effect by reducing ROS production via inhibition of NADPH oxidase. The present study intended to demonstrate effects of cisplatin on hepatic pro-oxidant/antioxidant systems and to investigate protective effects of APO against cisplatin-induced hepatotoxicity.