A 30-year-old woman with chest discomfort at swallowing and occasional vomiting was referred to our department with a diagnosis of esophageal submucosal tumor. CT visualized a mass 70 mm in diameter in the middle esophagus. Esophagogastroduodenoscopy revealed a pedunculated submucosal tumor, and endoscopic resection was considered. As the size of the tumor was so large, retrieval of the resected specimen via the stomach following incision, laparotomy was planned. En bloc resection by endoscopic submucosal dissection with a Hook-knife was performed. Retrieval of the resected specimen was carried out as planned. The specimen, which was 53×48×43mm in size with a distinct margin, was diagnosed as leiomyoma derived from the muscularis mucosae histologically. Her postprocedural course was uneventful. Endoscopic resection can be chosen when an esophageal submucosal tumor is pedunculated with abundant mobility, making it possible to avoid invasive surgery.