Mounier-Kuhn syndrome (MKS) is a syndrome char- acterized by the expansion of the trachea-bronchus, recurrent respiratory tract infections, and bronchiecta- sis. Herein, two cases were presented with MKS, as a rare disease. For years, cases had been followed up as asthma/chronic-obstructive-pulmonary-disease. In the radiological examinations of cases, there were bronchiectasic areas, and the growth of rare bacteria in bronchial secretions. The two women were diag- nosed as MKS when they were 43 and 63-yrs-old respectively, with severe enlargement of the tracheal and main bronchus diameter in the thoracic radiolo- gy. A tracheal stent was placed in case-1, and alt- hough her symptoms were relieved, we stopped trying the procedure because of the recurrent displacement of the stent caused by hemoptysis. Case-2 had poly- cythemia with no hypoxemia. Both cases were given supportive therapy including bronchodilator, muco- lytic, prophylactic antibiotic to control infection and vaccine immunization. As a result MKS should be kept in mind in the distinctive diagnosis of treatment resistant bronchospasm.