PURPOSE: To compare high-resolution CT (HRCT) findings of bronchiectasis caused by tuberculosis and due tocauses other than tuberculosis. MATERIALS AND METHODS: We retrospectively evaluated the HRCT findings of 93patients with bronchiectasis (in 40 patients caused by tuberculosis, and in 53 due to nontuberculous causes).Diagnostic bases for tuberculous bronchiectasis were positive sputum AFB or the presence of radiological findingsof pulmonary tuberculosis, plus a history of antituberculous chemotherapy. HRCT findings were analyzed andcompared in terms of disease extent, site, type, distribution of bronchiectasis, severity of bronchial dilatation,and bronchial wall thickening . RESULTS: Compared with nontuberculous bronchiectasis, the tuberculousbronchiectasis group showed more frequent upper lobe involvement, varicose type bronchiectasis, fibrotic band andcalcification, adjacent pleural thickening, bronchovascular distortion, and paracicatricial emphysema (p<0.05).The nontuberculous bronchiectasis group more frequently involved the lower lobe and showed a higher frequency ofcystic type bronchiectasis (p<0.05). The two groups showed no differences in the frequency of bilateral orwidespread involvement and in the severity of bronchial wall thickening and bronchial dilatation. CONCLUSION: Inpatients with bronchiectasis, HRCT findings of upper lobar distribution, fibrotic changes and calcification,traction or varicose type bronchiectasis, bronchovascular distortion, paracicatricial emphysema, and adjacentpleural thickening suggesta tuberculous origin.