INTRODUCTION: Closed laryngeal trauma is rare, but calls for rapid and effective management. It is seen most commonly after automotive accidents, with sports injuries contributing a very small share. Therefore, pneumomediastinum has hardly ever been reported as a complication of closed laryngeal trauma resulting from sports injuries. CASE REPORT: A 23-year-old man presented at the emergency department of the otolaryngology service of the University Hospital of São Paulo with worsening pain and increasing girth of the neck. The symptoms had started 3 days earlier when an ornamental jump went wrong during a bodybuilding practice session; first aid had been given at the time. Physical examination revealed subcutaneous emphysema in the neck, and imaging showed pneumomediastinum, a rare complication of closed laryngeal trauma. The patient was treated conservatively as advised in the literature, with total regression in 2 weeks without any complications. Keywords: Trauma of the Larynx; Dysphonia; Trauma in Sports; pneumomediastinum.