BackgroundMounier Kuhn's syndrome is a rare and congenital disease. It is characterized by an increase in the size of the trachea and main bronchi caused by a congenital disorder of the connective tissue and smooth muscles of these structures, the distal bronchial tree is usually normal. Its diagnosis is accomplished with the use of Computed Tomography (CT). It can be associated with other congenital conditions, which makes the understanding of its physiopathology more complicated. Its clinical features vary from being asymptomatic to severe respiratory distress. However, therapy remains conservative [1].