Gastric leiomyoma is an uncommonly found benign submucosal neoplasm which may cause hemorrhage in rare cases. A 67-years-old patient was admitted to our attention due to two episodes of hematemesis and melena occurred in the previous two days. Esophagogastroduodenoscopy showed a giant semi-pedunculated gastric polyp (diameter of 4 centimeters) located at the distal body. A large ulcer with a clot was seen on the polyp. We treated endoscopically the giant polyp using the new two-steps-technique recently described by us for the treatment of the large pedunculated gastric and colorectal polyps, and the polypectomy was successfully performed without immediate or delayed complications. Histological evaluation of the transected polyp revealed morphology according to a gastric submucosal leiomyoma. Endoscopic control, performed one and four weeks and 12 months later, showed complete reepithelization of the gastric mucosa, without any sign of endoscopic, endosonographic and histological recurrence of the disease. This case report shows that our endoscopic approach may be successfully used also for giant semi-pedunculated gastric polyps.