Abstract: The influence of Zinc (Zn) on Cadmium (Cd) intoxication was investigated in male rats. The exposure of the rats to Cd (2.2 mg kg-1 CdCl2, injected subcutaneously 4 times weekly for 2 months) caused alterations in ultrastructure of liver as manifested by deterioration of mitochondrial cristae, deposition of large amount of collagen fibrils and a hypertrophy of Kupffer cells accompanied by presence of large sized lipid droplets in their cytoplasm. On the other hand, the blood hydroperoxide level, concentrations of Zn, Cd and reduced Glutathione (GSH) in the liver were increased during the treatment period with Cd. On the other hand, blood GSH level and hepatic catalase activity decreased in the rats injected with Cd. Moreover, treatment with Cd produced significant increases in plasma Aspartate Aminotransferase (AST), Alanine Aminotransferase (ALT), gamma Glutamyl Transferase (γ GT) and alkaline phosphatase activities and bilirubin concentration. Administration of Zn (2.2 mg kg-1 ZnCl2 injected s.c. 4 times weekly for 2 months) one hour prior to cadmium exposure ameliorated the toxic effects of Cd. Zn alleviated the elevation of hydroperoxide level, alterations in ultrastructure of liver and hepatic enzymes and Cd accumulation induced by Cd. We conclude that Zn could serve as a physiological antioxidant against cadmium-mediated oxidative stress.