Abnormal liver function persisting late after allogeneic BMT is usually attributed to chronic GvHD, viral hepatitis or drug toxicity. We describe a patient who had negative hepatitis serology, was on no hepatotoxic medication, had no evidence of GvHD but had abnormal liver function 15 months post MBT. She was diagnosed as having grade IV hemosiderosis of the liver. Her total red cell support had only been 52 units. We therefore postulate that in a proportion of patients receiving allogeneic BMT impaired intestinal iron absorption may be an important cause of hemosiderosis.