A 9 yr old male neutered Staffordshire bull terrier with a history of poorly controlled hyperadrenocorticism, urinary tract infections, and emphysematous cystitis (EC) was presented to a veterinary referral teaching hospital for vomiting. Abdominal radiographs revealed EC and a pneumoperitoneum. The urinary bladder was found to be intact based on ultrasound and a pre- and postiohexol contrast computed tomography study with retrograde contrast cystogram. Urine culture confirmed the presence of a recurrent Escherichia coli urinary tract infection. The patient was managed medically, primarily as an outpatient, and had complete resolution of all problems. This case represents an extremely rare form of EC with pneumoperitoneum, without evidence of concurrent urinary bladder rupture. Only six similar cases have been reported in humans, with no previous cases reported in veterinary medicine. This case demonstrated that surgery is not necessarily indicated in all cases of pneumoperitoneum. The patient remained alive at 2 mo follow-up, with no evidence of recurrence of EC.