A 68-year-old man with aortic aneurysm who had repeated episodes of obstructive bronchopneumonia is reported. Serial chest X-rays revealed infiltrative shadows in the left lower lung field. A thoracic computed tomogram demonstrated a dissecting descending aorta compressing the left lower bronchi and abnormal shadows, probably inflammatory, distal to the obstructions. Because of signs of impending rupture of the dissected aorta, surgical repair was performed and there has been no recurrence of respiratory infection since.