Urinary bladder torsion is a surgical emergency in dogs. Ischemia of the urinary bladder wall may result from strangulation of the arterial and venous blood supply and from overdistension. Subtotal resection of the urinary bladder, preserving only the trigone area and the ureteral openings, and colonic seromuscular augmentation can be used to successfully treat urinary bladder torsion in dogs.