Testicular teratoma is a rare tumor in children. We recently encountered two boys, aged 18 months and 2 years respectively, with this tumor. Sonography revealed an intratesticular mass in both. The first revealed a predominantly cystic lesion with echogenic components along its wall. The second showed a complex mass occupying most of the right testicle, and containing several areas of calcifications and cysts. Excellent pathologic correlation was obtained in both. Preoperative diagnosis of testicular teratoma is possible if the characteristic features are recognized. The prognosis is good following orchiectomy in the pediatric patients.