Inflammatory pseudotumor is the most frequent primary lung tumor in children under the age of 16. Inflammatory pseudotumor of the lung is usually peripherally located, but lesions may rarely be endobronchial. We report here the case of a five-year-old girl with unresolving pneumonia and atelectasis at the left lower lobe. Radiologically, atelectasis due to bronchial obstruction was considered, and bronchoscopic and histopathological investigations confirmed the definite diagnosis.