Background and objective: This study was designed to determine the protective effects of zinc on halothane-induced hepatotoxicity. Methods: Forty-five male Sprague-Dawley rats were divided into three groups. The halothane group received normal drinking water and diet; the zinc-halothane group received 227 mg L-1 zinc sulphate in the drinking water and diet for 2 weeks; and the control group received normal diet and water. At the end of 2 weeks, rats were housed in an anaesthesia box and 1 MAC (minimum alveolar concentration) halothane was administered at 6 L min-1 in room air for 2 h. This was repeated 48 h later. After the rats were sacrificed, we measured alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, gamma-glutamyl transpeptidase, glutathione-S-transferase, serum electrolytes and bilirubin in samples. The degree of liver toxicity was assessed by light microscopic examination. Results: We demonstrated a reduction of alanine aminotransferase, aspartate amino transferase, glutathione-S- transferase levels and a reduction in liver damage in the zinc-halothane group. Conclusion: The study concludes that zinc has the potential to alleviate the toxic effects of halothane in rat liver. © 2008 Copyright European Society of Anaesthesiology.