We report a case of esophageal schwannoma in a 46-year-old woman who presented with rapidly progressive dyspnea and dysphagia. Chest computed tomography showed a large mediastinal mass, which was extrinsically compressing the trachea, widely adjacent to the upper thoracic esophagus. We performed an axillary right thoracotomy to enucleate the tumor, which was located in the esophageal muscle layer. A definite diagnosis of esophageal schwannoma was made from the pathologic findings, which included positive immunohistochemical staining for S-100 protein and negative staining for c-kit and CD34.