A 15-year-old Warmblood gelding was presented with macroscopic hematuria and stranguria symptoms for two months. Cystoscopy revealed a pedunculated cauliflower-like mass, flowing from the right ureteral orifice into the bladder. Ureteroscopy showed a right dilated ureter (2.3 mm). The ureteral lumen mucosa was smooth and the mass had its origin approximately 10 cm cranial from the orifice. The right kidney was macroscopically on ultrasound within normal range. The mass was removed transendoscopically by means of a cautery snare leaving a small part at the base. Histopathological analysis identified it as a mucosal polyp. Recovery was uncomplicated and the gelding was discharged three days after surgery. A follow up 5 months later showed no signs of inflammation and the remaining small stalk in the right ureter.