Primary solid tumor which growing in the mesentery or omentum is rare, mesodermal originated, is not fixed, movable easily. It does usually not cause symptom unless complications such as intestinal obstruction, torsion, and rupture. A 42-years old patient had a solid tumor of pelvic and abdominal mass, which was considered as uterine myoma or parasitic myoma. Laparotomy revealed a solid tumor in the greater omentum, about 8cm, and histologically diagnosed as a leiomyosarcoma. We report a case of primary greater omental leiomyosarcoma with brief review of literatrure.