Inflammatory pseudotumors of the lung are a group of non-neoplastic tumors, which are mainly of parenchymal origin and rarely endobronchial. We report a case of a 9-year-old girl who presented with left-sided tension pneumothorax and subcutaneous emphysema. After emergency management, chest computed tomography revealed an ill-defined left lung mass. Rigid bronchoscopy revealed a mass occluding the left main bronchus at the origin of the left upper lobe bronchus. Initially, the mass was thought to be a foreign body granuloma. Few weeks later, the child presented with recurrence of the same clinical, radiologic, and bronchoscopic outcomes. Histologic examination after the repeat bronchoscopic excision revealed the lesion to be consistent with inflammatory pseudotumor. Left upper lobectomy was performed with a complete resolution of symptoms and no recurrence was observed during the 2 years of follow-up. To the best of our knowledge, this is the first reported case of inflammatory pseudotumor presenting with tension pneumothorax.