Hepatolenticular degeneration, commonly known as Wilson disease, is an autosomal recessive inherited disease of abnormal copper metabolism, characterized by the accumulation of copper in the body due to decreased biliary excretion of copper from hepatocytes. Wilson disease protein, ATP7B, functions in copper excretion into bile and in copper secretion to the bloodstream coupled with ceruloplasmin synthesis. Various kinds of mutations of ATP7B cause Wilson disease. Wilson disease is a rare genetic disease that can be treated pharmacologically. Recognition and prompt diagnosis are very important, because Wilson disease is fatal if left untreated. In this review, I summarize the pathogenesis and management of Wilson disease. 