The kidney is the appropriate critical organ for indicating chronic exposure to chromium compounds. The present work investigates the effect of dose-dependent hexavalent chromium concentration in various tissues of rats, the disturbances in metabolism of zinc and copper in liver and kidney, and histopathological changes in kidneys. White Wistar rats were used. Animals were injected intraperitoneally at a dose of 0.5 and 5mg Cr/kg as K 2CrO 4. The animals were sacrificed after single and repeated doses at 24h after the last injection. Disturbances in the metabolism of zinc and copper in the kidney of rats occur when the concentration of chromium in this organ attains about 30μg Cr/g. An increase in urinary output of these essential metals is a more sensitive indicator of nephrotoxicity than ultrastructural damage of kidney.