The pneumomediastinum is the presence of free air or gas in the mediastinal space. It occurs secondary to trauma that allows air to enter the mediastinum and into the subcutaneous tissue leading to generalized or localized subcutaneous emphysema.This paper describes a case of generalized subcutaneous emphysema secondary to a pneumomediastinum in a neonate cat attended at the Veterinary Hospital of the Federal University of Paraíba located in Areia-PB. A 10-day-old female feline, mixed breed (SRD), weighing 68 grams, had a history of sudden, widespread air in the subcutaneous tissue throughout the animal's body, observed every time it was fed. At the laboratory it was performed the air aspiration using syringe and needle. In order to reach t...