Introduction This study aimed to evaluate the etiological factors and their effects on long-term clinical outcomes in patients with iatrogenic ureteral injury (IUI). Material and Method Twenty-seven patients who underwent surgery because of IUI were evaluated between January 2011 and April 2018. Patients were classified according to the time of diagnosis and the need for reoperation after the urologic intervention. The IUI cases detected during gynecological surgery were called ‘perioperative’ IUI, and those diagnosed late as ‘postoperative’ (delayed) IUI. The IUI type was categorized as ‘cold transection’ due to surgical dissection or ligation and ‘thermal injury’ if it depended on any energy-based surgical device. Results Postoperative diagnosed cases consisted of exclusively after laparoscopic surgery (p=.025). Patients with thermal injury to the ureter were mostly diagnosed postoperatively (p= .021). Patients who underwent endourological intervention, 31.25% (N = 5/16) were diagnosed during gynecologic surgery, and 68.75% (n = 11/16) were diagnosed postoperatively. For open reconstructive surgery, these rates were observed to be 72.72% (n = 8/11) and 27.28% (n = 3/11), respectively (p=.034). IUI was due to thermal injury in all patients who developed complications after the urological intervention (p = .046), and the first urological intervention was endoscopic double loop stenting (p = .005). One of these patients was diagnosed in the perioperative period and seven in the postoperatively (p = .016). Conclusion Treatment success rates are low in patients who underwent endourological intervention after thermal IUI. Therefore, surgical techniques in which the traumatic ureter segment is excised should be preferred to avoid complications. Key Words Ureter, Iatrogenic, Thermal Injury, Iatrogenic Ureteral Injury, Endourological Intervention.