A case is reported of a 40 year-old woman with a ''form fruste'' of tuberous sclerosis, multiple angiamyolipomas of the kidney, and an angiomyolipoma of the liver. On magnetic resonance imaging the hepatic mass was markedly hyperintense to liver on short TW/short TE spin-echo sequence. Spiral computed tomography during arterial portography showed hepatic mass in the right hemiliver with areas of negative attenuation values suggesting fat content. Pathologic examination of the resected specimen confirmed the diagnosis of an angiomyolipoma of the liver. Computed tomography during arterial portography is a commonly performed preoperative imaging modality. Therefore, recognition of angiomyolipoma of the liver by this technique is important, because this benign mesenchymal neoplasm may not require resection.