Wilson's disease is a rare, multiorganic genetically coded disorder, induced by impaired copper transport. The recent identification of the disease gene and the discovery of gene product--copper transporting P-type ATPase that is integrate membranous protein has contributed greatly to better understanding of the pathogenesis. This protein is probably essential for incorporation of copper into ceruloplasmin and for its biliary excretion. Multiple mutations of Wilson's disease gene are responsible for the excess of so called "free" copper which is toxic to tissues. Copper toxicity involves first of all, functional disorders of many enzymatic systems, particularly those of respiratory chain enzymes. In the central nervous system, a special kind of copper toxicity is medicated by astroglia, so that a direct, harmful effect of both copper and ammonia on the brain is observed. The authors present a current review on biochemical mechanisms of copper toxicity and physiopathological significance of the CNS astroglia in Wilson's disease.