Mounier-Kuhn syndrome or congenital tracheobronchomegaly is a chronic airway condition which for currently unknown reasons mostly affects males. It is commonly overlooked on conventional chest X-rays, and is considered to be rare, but the prevalence might be higher as commonly assumed. The hallmark of it is a dilatation of the main airways which frequently, but not always, causes marked, mainly respiratory, symptoms, and patients usually present with varying degrees of recurrent infections, breathlessness, haemoptysis, dyspnoea. Although at least 200 case reports have been published, there have been only a few attempts to review them, and none in the last 20 years. Due to the lack of clinical trials and wide variability of case-report format, a systematic review was deemed not feasible, therefore PubMed and Medline databases were searched using terms "Mounier-Kuhn syndrome", "tracheobronchomegaly", "tracheomegaly", and "bronchomegaly", without any time restrictions, to summarize currently known facts about the syndrome. To the authors' best knowledge, the result is currently the most comprehensive review of previously published literature about the congenital tracheobronchomegaly, and summarizes what's known about symptoms, prevalence, disease associations, and treatment options for this syndrome.