Although intraperitoneal teratomas are rare, teratomas of the greater omentuma are seldom reported. A single case of omental teratoma with torsion in a 26-month-old girl is reported. The patient presented with abdominal pain and a palpable mass. Ultrasonography and CT of the abdomen showed a large cystic mass with a non homgenious solid component composed of fat and calcification. The lesion was surgically excised. Pathology revealed a mature omental teratoma. The hospital course was uneventful.