BACKGROUND To assess the effect of endobronchial radiation guided by fiberoptic bronchoscope for malignant airway obstruction. METHODS Sixty-five patients with lung cancer and malignant airway obstruction were investigated. After routine bronchoscopic examination , the brachytherapy catheter was inserted through biopsy channel and the tip was fixed onto the obstructing malignancies. Then radiotherapy was performed with 192 Ir at a dose of 628 Gy distributed among 225 points. The treatment was rendered weekly in a sequence of 3 weeks as one course. The chest X-ray and bronchoscopic assessment were made 1 and 4 week after finishing radiation therapy. RESULTS X-ray assessment :CR ,PR and MR were 23. 08 %(15 cases) ,43. 08 %(28 cases) and 18. 46 %(12 cases) respectively , with 84. 62 %of total effective rate (CR + PR +MR) . Bronchoscopic assessment : CR , PR and MR were 38. 46 %(25 cases) , 43. 08 (28 cases) and 13. 85 %(9 cases) respectively , with 95. 38 % of total effective rate. CONCLUSIONS The endobronchial radiation guided by fiberoptic bronchoscope has better reopening effect and less complications for malignant airway obstruction in the patients with lung cancer.