Necrotizing fasciitis is a serious, rapidly progressive infection of subcutaneous tissue and fascia. While free intraperitoneal air is known to occur in peritoneal dialysis patients, dissection of this air into the abdominal wall mimicking the subcutaneous emphysema of necrotizing fasciitis has not previously been reported. We herein report the first case of pseudonecrotizing fasciitis due to dialysate fluid and air leak in a patient on peritoneal dialysis and discuss features differentiating this process from true necrotizing fasciitis.