Malignant transformation of craniopharyngioma is a rare event; only 3 cases have been reported in children, all in the Japanese literature. The authors describe 2 additional pediatric cases. Treatment in both of these cases consisted of multiple resections and external beam radiation therapy (EBRT). Malignant transformation occurred 7 and 8 years after EBRT. The authors also review another 6 cases in adults. A possible causative association with radiation therapy is discussed. As radiation is currently an important option in the management of craniopharyngiomas, this association requires further study.