COPD is a very common disease and has increseased tendency globally as well as in Vietnam. Recently studies shown that sequel of pulmonary tuberculosis (PTB) is one of the risk factors of COPD, however, the relationship between two conditions is still confusing especially in clinical practice in the high tuberculosis burden countries. Method: This study based on cross-sectional observation with control group to investigate the clinical and laboratory differences of the COPD patients with and without sequels of inactive PTB. Study subjects: COPD patients met with GOLD criteria those were classified into 2 group: Group I - 30 patients with sequels of inactive PTB and group II - 30 patients without these sequels. Results: productive cough was more common in the group I (93.3 percent vs 66.7 percent, P 0.05). Dyspnea MRC score was more servere in the group I (3.5 + or - 0.9 vs 3.0 + or - 0.9, p0.05). Excercise capacity evaluated by 6-MW distance was more decreased in the group I (309 + or - 81m vs 372 + or - 82m, p0.05). SVC, FVC and FEV1 was also significantly lower in the group I (82.9 + or - 24 vs 97.2 + or -:24.6
82.4 + or - 24.3 vs 95.2 + or - 24.7 and 50.9 + or - 22.1 vs 64.7 + or - 21.4
p0.05). On thoracic HRCT signs of bronchiactasis and emphysema was more frequent and also more servere in the group I with dominant emphysema polymorphism.