Mounier-Kuhn syndrome or tracheobronchomegaly is a rare disease characterized by marked dilation of the trachea and proximal bronchi with recurrent lower tract respiratory infections. Computed tomography and bronchoscopy are the key tools to accomplish the diagnosis. This is a condition with a clinical polymorphism, symptoms vary from minor with preserved respiratory function, to very severe with life threatening exacerbations leading to respiratory failure and premature death. The treatment is mainly symptomatic, stenting or surgery are reserved to extreme cases.Herein, we report two cases of the same condition with different clinical signs and diverse outcome.