We evaluated a 72-year-old woman who was experiencing dysphagia. Esophageal leiomyosarcoma was diagnosed by barium meal study, upper gastrointestinal endoscopy, endoscopic ultrasonography (EUS), by computed tomography (CT). A barium meal study and esophagoscopy performed 3 months before the diagnosis of esophageal leiomyosarcoma showed no abnormalities. Therefore, the tumor appeared to have grown rapidly during the 3-month period.