A case of leiomyosarcoma of the stomach developed in 15-year old child reports with a review of the literature. The old child visited to Hospital on 15th. Sept. 1972 with epigastric discomfort, dizziness and headache, in digestion of 6 month prior. The upper G-I series showed a enlargement of polypoid mass in the posterior wall of the greater curvature of the gastric body and ulcerative lesion in the central part of the itsmass. Ulcerative margin was irregular. Mucosal patterns of the stomach were preserved save for polypoid region seems to be some widen of mucosae. Numerous nodular calcifications were demonstrated in the extralumen of the greater curvature of the gastric body.