Small bowel leiomyosarcomas are uncommon but potentially curable tumors often diagnosed at an advanced stage. Twenty such lesions were studied, and 19 of these produced symptoms and signs. Clinical findings included abdominal pain in 17 (85%), rectal bleeding in 8 (40%), anemia in 7 (35%), intraperitoneal perforation in 6 (30%), and abdominal mass in 4 (20%). Various abdominal x-ray examinations revealed nonspecific abnormalities (ileus, bowel obstruction, abdominal mass) in about half the cases in which they were obtained, but in only one instance was the correct diagnosis of small bowel tumor made preoperatively. Five of 12 patients undergoing resection in hope of cure survived five years. These tumors tend to metastasize by hematogenous dissemination, peritoneal implantation, local invasion, and, uncommonly, lymphogenous spread. Wide small bowel resection with adjacent mesentery is suggested for most lesions. Five year survival following resection approximates 50% in reported series.