A three-year-old, intact male, Siberian husky was evaluated for a two day history of dysuria. Sonographically there was an anechoic cyst-like structure in the urinary bladder. The abnormality appeared to be a 'cyst within a cyst', which is a characteristic ultrasonographic feature of ureterocele in humans. Ultrasonography may be a useful means of establishing a diagnosis of ureterocele in dogs.