The aim of this study was to determine the ability of bronchial brushing in rapid diagnosis of pulmonary tuberculosis in patients with negative sputum smear.this retrospective study was performed on 188 patients who were suspected of pulmonary tuberculosis and had undergone fiberoptic bronchoscopy during the period of 1990 to 1996 in Kerman university No.1 . Although their history, physical and radiological finding were suggestive of active pulmonary tuberculosis , the sputum smears were negative in the majority of the cases. The specimens obtained trough fiberoptic bronchoscopy by bronchial brushing were stained by Zidhl-Neelson method and were examined for the presence of AFB. Among 180 patients , 65 cases (35℅) were positive for AFB. These patients also were studied for radiographic changes. The most common radiological patterns were first, consolidation and then, infiltration . Since this technique can be performed in just 3 days it can be used for rapid diagnosis in such patients.