Coal tar is a significant product generated from coal pyrolysis. Coal tar can be utilized as raw materials for various industries such as synthetic fiber, dyestuff, medication, coating and national defense. It is also a type of raw materials from which phenols, naphthalenes and anthracene can be extracted for the production of washing oil, cementitious agents, antiseptic agents, and catalytic hydrogenated to produce gasoline, diesel oil, etc. Therefore, the present study was designed to investigate the possibility of coal tar creosote to induce oxidative stress and biochemical perturbations in rat liver and the role of rosemary in ameliorating its toxic effects. Male Wister Albino rats were randomly divided into four groups of 10 each, group I served as control; group II treated with rosemary (10 ml of extract/kg BW for 21 days), group III received coal tar creosote (200 mg/4ml olive oil/kg BW for 3 days) and group IV treated with both rosemary and coal tar creosote. The local committee approved the design of the experiments, and the protocol conforms to the guidelines of the National Institutes of Health (NIH). The administration of coal tar creosote significantly caused elevation in lipid peroxidation (LPO) and reduction in the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST). A significant decrease in reduced glutathione (GSH) content was also observed. Liver aminotransferases (AST and ALT) and alkaline phosphatase (AlP) were significantly decreased while lactate dehydrogenase (LDH) was increased. Rosemary treatment to coal tar creosote treated rat decreased LPO level and normalized SOD, CAT and GST activities, while GSH content was increased. Also, liver AST, ALT, AlP and LDH were maintained near normal level due to rosemary treatment. In conclusion, Rosemary has beneficial effects and could be able to antagonize coal tar creosote toxicity.