We report on an 11-year-old girl with cystic fibrosis who presented with thoracic pain and an extensive subcutaneous emphysema and subsequently developed progressive respiratory distress. The chest computed tomography revealed a huge pneumomediastinum. Due to the development of severe respiratory failure, urgent needle thoracocentesis was necessary that resulted in only temporary improvement. Therefore, under general anesthesia two mediastinal drains were introduced. Using active suction, the size of the pneumomediastinum decreased gradually and the drains were removed after 3 weeks. Here, we describe an extremely rare situation, when acute surgical intervention was necessary in a child with spontaneous pneumomediastinum.