Pulmonary bronchogenic cyst in adults is rare and the typical appearance is a sharply circumscribed, round or oval nodule or mass, usually in the medial third of the lungs. Bronchial polyps are rare histopathologically distinct nonneoplastic endobronchial lesions and are classified as multiple papillomas, solitary papillomas, and inflammatory polyps. We herein report a patient with polypoid endobronchial lung cyst. A 68-yr-old woman presented with a discomfort and pain in the right upper chest of four weeks' duration. Chest radiography revealed a cystic lesion in the right upper lung. Computed tomography revealed a 4 x 5 cm sized large cyst. Neither enlarged mediastinal lymph nodes nor extrabronchial involvements were observed. Flexible bronchoscopy revealed a peduncular polyp about 2 cm in length originating from the anterior segment of right upper lung. After bronchoscopic removal of polyp, cystic lesion of the right upper lung disappeared.