The papillary adenoma of the lung is a rare benign neoplasia with intraparenchymal localisation and is thus, in general, difficult to access for biopsy diagnosis. Due to the rarity of this lesion, the intra-operative histological diagnosis by frozen section may be problematic. We report on a 75-year-old male patient with a lung nodule, biopsied by means of bronchoscopy with TBNA. The tissue obtained was processed histologically as a cell block and examined microscopically. The diagnosis of a papillary adenoma was made. Our case is the first report on the diagnosis of a papillary adenoma of the lung by TBNA biopsy. For our patient with impaired lung function the diagnostic procedure described here represented a less invasive alternative to the diagnostic evaluation by surgery with intraoperative frozen section examination. This case shows that the TBNA biopsy combined with processing of the tissue as a cell block may represent a contribution to the appropriate management of the patients and serve as an aid for therapy planning.