Mounier-Kuhn syndrome (MKS) or congenital tracheobronchomegaly is a rare disorder characterized by marked dilatation of the trachea and main bronchi, bronchiectasis, and recurrent respiratory tract infections. The etiology of this disorder is uncertain and the clinical presentation is variable. The diagnosis is usually made based on the characteristic computed tomography (CT) scan findings. This report describes a case of a 43-year-old man presenting with persistent cough and recurrent lower respiratory tract infections since childhood associated with copious amounts of purulent sputum, difficulty in breathing, and weight loss. In addition, he reported palpitations, dyspnea, orthopnea, abdominal and lower limb swelling. The chest X-ray showed a dilated trachea (35mm) and bronchi (26mm (right) and 27mm (left)) with cystic bronchiectasis and reticulolinear opacities predominantly involving the middle and lower lung zones. Chest CT scan confirmed the diagnosis of MKS as evidenced by dilated trachea and bronchi complicated by diverticula formation. Electrocardiogram, echocardiography and abdominal ultrasound scan showed features of right-sided heart failure secondary to pulmonary hypertension. MKS, although rare, should be considered as a possible diagnosis in patients presenting with productive chronic cough, recurrent pneumonia, or incomplete response to appropriate antibiotic therapy for pneumonia.