We encountered 3 patients with spontaneous pneumomediastinum. The patients were a 14-year-old female, a 16-year-old male and an 18-year-old male. All 3 were previously healthy. They complained of chest pain or dyspnea. On admission, physical examination revealed subcutaneous emphysema. Chest computed tomography (CT) revealed pneumomediastinum and subcutaneous emphysema. All patients were treated with rest and all recovered in 7 to 9 days without any complication. Spontaneous pneumomediastinum is an uncommon, usually benign, self-limited disorder that usually occurs in young adults without any apparent precipitating factor or disease. Most patients require only conservative treatment.