Endobronchial hamartoma is a rare, benign tumor usually associated with pneumonitis and atelectasis caused by obstruction. Lobectomy is sometimes performed even if the tumor is benign. Transbronchial endoscopic surgery is usually performed for patients with a small endobronchial hamartoma. We report our treatment of a large hamartoma completely obstructing the patient's left main bronchus. The tumor was partially resected, and that remaining was resected by transbronchial endoscopic surgery. No finding of recurrence of the endobronchial hamartoma was detected by endoscopy or biopsy for 3 years. A combination of bronchoplasty and transbronchial endoscopic surgery benefits patients with large endobronchial hamartoma by preserving the lung parenchyma.