We report three cases of giant gastric leiomyosarcoma. Diagnosis was made prior to surgery using various diagnostic modalities. The patients were two women (77 and 77 years old) and one man (40 years old) whose chief complaints were abdominal pain, anorexia, and tarry stool. All patients presented with a large palpable mass in their upper abdomen at the time of admission. Based on characteristic findings from a gastric barium study, computed tomography (CT), and angiography, the patients were diagnosed as having gastric leiomyosarcomas displaying extramural growth. In the first case, a patient • received a total gastrectomy, while local resection was performed in the second case because of pedunculated extragastric development. In the third case, total gastrectomy was combined with splenectomy and resection of the pancreatic tail. Twenty-two months after the original operation, the first case had multiple liver metastases. We present the three cases here, and review the literature.