A case of cystic mesenchymal hamartoma in a 2 yr old boy is presented. The overall angiographic appearance closely resembled that of the more common renal angiomyolipoma, with the addition of multiple focal avascular areas representing the cystic component of the lesion. The coexistence of these angiographic findings in a young patient with an otherwise asymptomatic upper abdominal mass should suggest cystic mesenchymal hamartoma.