Wilson's disease is an autosomal recessive inherited disorder characterized by increased body store of copper due to deranged copper metabolism. In wilson's disease, hepatic manifestations can be detected in earlier stage than neuropsychiatric manifestations. Though there were several reports of Wilson's disease presenting hepatic symptoms in Korea, the case of Wilson's disease presenting acute hepatic failure at the age over 30 years was not reported. Here, we report a case of Wilson's disease presenting acute hepatic failure in a 31-year-old man. He was admitted to our hospital due to jaundice and ascites. Main findings were the presence of Kayser-Fleischer ring, decreased serum ceruloplasmin, worsening liver function and Coomb's negative hemolytic anemia, but no neuropsychiatric symptoms were observed. The pathologic finding of the liver revealed cirrhotic change and severe cholestasis with a periportal hepatocytes containing copper-positive granules. He was successfully treated with penicillamine. (Kor J Gastroenterol 2000;35:126 - 131)