CASE PRESENTATION: Previously healthy 6 year old African American male with 1 month of cough and 1 day history of chest pain, in the emergency room he presented nor hypoxia, fever or dyspnea. A chest x-ray showed complete atelectasis of the left lung, a CT scan of the chest confirmed the complete collapse of the left lung and showed an abrupt blockage of the left main bronchus. A bronchoscopic evaluation found complete occlusion of the left main bronchus by soft material that extended from the left main stem into the left upper, and lower lobe bronchus. The histology showed mucus material with numerous necrotic and viable eosinophils and neutrophils, Charcot-Leyden crystals, Curschmann spirals, and rare Creola bodies. Stain for fungi were negative. The patient recovered well from the extraction of the mucus plug, and showed radiological improvement, he was discharged on penicillin, inhaled and oral steroids.