A 14-month-old white male was diagnosed as having angiosarcoma of both the liver and spleen. At 17 months he developed pulmonary metastases and died. There was no apparent environmental or hormonal exposure either prenatally or during infancy. The malignant tumor probably arose from its benign counterpart (hemangioendothelioma), which was found in the spleen. This is the fifth case reported of splenic angiosarcoma in the pediatric age group (18 years or younger).