Flexible fiberoptic bronchoscopy (FB) is a recently available tool for the investigation of pediatric pulmonary diseases. Endobronchial tuberculosis (ETB), a common complication of primary tuberculosis, has traditionally been diagnosed by clinical findings of bronchial obstruction and roentgenographic evidence of bronchial involvement. A retrospective study was conducted to determine the incidence of endobronchial tuberculosis in children diagnosed by traditional means as having uncomplicated primary tuberculosis. Analysis of the bronchoscopic findings of 36 children with active pulmonary tuberculosis revealed that 15 (41.7%) had endobronchial involvement. Significantly 10 (28%) children who had no clinical or radiologic evidence of endobronchial involvement had endobronchial tuberculosis; 4 (11%) had early and 6 (17%) had advanced ETB by FB. There were 6 patients with radiologic evidence suggestive of ETB, which was confirmed by FB in 5 patients. One child had a obstruction of a bronchus by mucus. The mucus was removed with subsequent expansion of the distal lung segment. Complications of the procedures were mild. FB is a safe procedure and a valuable aid for the rapid diagnosis of ETB.