Abstract: Here, we report what is to our knowledge the first documented case of epidural pneumatosis in the setting of Pneumocystis jiroveci pneumonia. Epidural pneumatosis is defined by air in the epidural space. Its common pathophysiologic development is from air leaking from pneumomediastinum through intervertebral foramina, although other mechanisms exist. Our patient, an 18-year-old man with acquired immunodeficiency syndrome, developed a striking epidural pneumatosis with associated pneumomediastinum as a complication of P jiroveci pneumonia. He was treated successfully with trimethoprim-sulfamethoxazole and prednisone, and he experienced no sequelae from the epidural pneumatosis. In fact, epidural pneumatosis generally is regarded as a benign phenomenon.