Endobronchial tuberculosis is granulomatous inflammation of the bronchial mucosa characterized by bronchial ulceration due to caseous necrosis. There is a good chance to expectorate cellular components of granulomas in the sputum. The author studied a cytologic series from 46 patients with endo-bronchial tuberculosis confirmed on fiberoptic bronchoscopic biopsy. The cytologic series consisted of 32 sputa, 41 washings, and 17 bronchial brushings, and were carefully screened for elongated epithelioid cells, Langhan's type giant cells, other multinucleated giant cells and caseous material. Elongated epithelioid cells were demonstrated in 9 sputa (28.1%), 30 bronchial washings (73.2%) and 11 brushing smears (64.7%). Langhans' giant cells were observed in two of 32 sputa (6.2%), six of 41 bronchial washings (14.6%) and four of 17 bronchial brushings (23.5%). The caseous materials were noted in 19 of 32 sputa (59.4%), 32 of 41 bronchial washings (78.0%), and 14 of 17 bronchial burshings (82.4%). It appeared that the pertinent cellular components of granulomas in sputa or bronchial secretions indicated a strong evidence of endobronchial tuberculosis of the lung.