A 73-year-old man was admitted to our hospital because of fever, productive cough and dyspnea on exertion in March 1998. He had been treated at our hospital for interstitial pneumonia. Chest radiographs showed consolidations and honeycomb shadows in both lungs. He also had a chronic subdural hematoma. After admission his respiratory state deteriorated and the chronic subdural hematoma increased in size and as a result, artificial respiration was needed. During intubation for bronchoscopy, we found protuberant white lesions in the tracheal mucous membrane, a biopsy of which showed amyloid deposition. Immuno-histochemistry revealed AL-amyloid, although there was no amyloid deposition else where. This was an idiopathic case in which localized tracheal amyloidosis probably developed in association with interstitial pneumonia.