For the diagnosis of bronchogenic cancer, there are many diagnostic methods including radiologic evaluation, bronchography, sputum cytology and biopsy. In 65 cases of histologically proven bronchogenic cancer in Seoul National University Hospital during the period from August 1966 to July 1971, the bronchographic cancer was analyzed, and its diagnostic accuracy was compared with other procedures. RESULTS : 1. The bronchography was carried out in 51 cases in which bronchial block was most frequent sign. 2. The overall diagnostic accuracy of bronchography was 90%, and according to the location revealed hilar 100%, middle 93% and peripheral 63%. 3. The bronchoscopy showed 74% accuracy when combined procedures of gross inspection, washing and biopsy have carried out. 4. The most frequent finding of plain chest film was circumscribed mass as in 24 cases.