A urinoma is a collection of urine surrounded by a fibrotic wall and, in the veterinary medicine, this condition is rarely reported. The aim of this study is to describe the clinical and therapeutic features of two cats with post traumatic urinomas, with particular attention paid to the imaging findings. In both patients, well-defined anechoic fluid collections in the retroperitoneal space were identified by ultrasound examinations and the laboratory tests suggested the urinous nature of the fluid. With excretory urography, the only relevant findings revealed were the abdominal and retroperitoneal loss of detail, whereas the combination of multiple techniques in Case 1 and the delayed study in Case 2, detected contrast leakage and fluid collections in the retroperitoneal space. Both patients fully recovered after either surgical or conservative treatments. In conclusion, different imaging modalities have been helpful to properly diagnose urinomas in cats and especially combined and/or delayed studies were of paramount importance for the final diagnosis.