Wilson's disease is a hereditary disorder of copper metabolism that results in the accumulation of copper in the body, primarily in the liver, brain, and cornea. Hepatocellular carcinoma, in contrast to other causes of cirrhosis, is seldom associated with Wilson's disease. We present a 12-yr-old boy with Wilson's disease in whom hepatocellular carcinoma was incidentally diagnosed in the pathologic specimen examined after liver transplantation.