Aim: Spontaneous pneumomediastinum (SPM) is the presence of free air in the mediastinum without any clear reason. It is a rare, self-limiting disease that occurs mostly in young men. Although radiographic imaging is usually sufficient for the diagnosis, thoracic computed tomography may be required in suspicious cases and to determine the etiology. The conservative approach is sufficient in the treatment. In this report, we present a 23-year-old male patient who presented to the emergency department due to chest pain and was diagnosed with spontaneous pneumomediastinum. Case: 23-year-old male patient presented to the emergency department with chest pain. His general condition was good, and he was conscious. Systemic physical examination and electrocardiogram were normal. Free air was detected in the paratracheal area on the posteroanterior (PA) chest X-ray. He was admitted to the thoracic surgery service for follow-up and treatment with the diagnosis of pneumomediastinum. Conclusion: Spontaneous pneumomediastinum should definitely be considered in the differential diagnosis of young patients presenting to the emergency department with chest pain. Clinical suspicion is the most valuable step for the diagnosis of spontaneous pneumomediastinum. Although PA chest X-ray is mostly sufficient for diagnosis, thoracic computed tomography is necessary to determine the etiology and follow-up.