Infection with hepatitis A virus can cause severe or even fatal illness in patients with chronic liver disease. Here we describe a seven-year-old girl who presented as acute liver failure and was diagnosed with Wilson's disease and later with coexistent hepatitis A infection. Wilson's disease was demonstrated on the basis of low ceruloplasmin, high urinary copper excretion, histological evidence of cirrhosis, and high biochemical estimation of liver copper concentration. Hepatitis A was diagnosed serologically. Our case suggests that acute hepatitis A may play a part in the acute decompensation seen in some cases of unrecognized Wilson's disease. We also emphasize the importance of prevention measures of hepatitis A infection in patients with chronic liver disease.