BACKGROUND: Iatrogenic ureteral injuries during colorectal surgical procedures are rare. Little is known about their incidence, associated outcomes, and predisposing factors. OBJECTIVE: The purpose of this study was to examine the trends of iatrogenic ureteral injuries in the United States over a decade, as well as their outcomes and risk factors. DESIGN: This was a retrospective study. SETTINGS: The nationwide inpatient sample from 2001 to 2010 was analyzed. PATIENTS: Included were patients with colorectal cancer, benign polyps, diverticular disease, or inflammatory bowel disease undergoing colorectal surgery. MAIN OUTCOME MEASURES: Trends of iatrogenic ureteral injuries occurring in colon and rectal surgical procedures were examined over a 10-year period. Mortality, morbidity, length of stay and total charge associated with ureteral injuries were analyzed on multivariate analysis. Finally, a predictive model for ureteral injuries was built using patient, hospital, and operative variables. RESULTS: An estimated 2,165,848 colorectal surgical procedures were performed in the United States over the study period, and 6027 ureteral injuries were identified (0.28%). The rate of ureteral injuries was higher in the second half of the decade (2006-2010) compared with the first half (2001-2005; 3.1/1000 vs 2.5/1000; p < 0.001). Ureteral injuries were independently associated with higher mortality (OR, 1.45; p < 0.05), morbidity (OR, 1.66; p < 0.001), longer length of stay (mean difference, 3.65 days; p < 0.001), and higher hospital charges by $31,497 (p< 0.001). Risk factors for ureteral injuries included rectal cancer (OR, 1.85), adhesions (OR, 1.83), metastatic cancer (OR, 1.76), weight loss/malnutrition (OR, 1.08), and teaching hospitals (OR, 1.05). Protective factors included the use of laparoscopy (OR, 0.91), transverse colectomy (OR, 0.90), and right colectomy (OR, 0.43). LIMITATIONS: This was a retrospective study from an administrative database. CONCLUSIONS: Iatrogenic ureteral injuries are rare complications in colorectal surgery; however, their incidence appears to be rising. Ureteral injuries are associated with higher mortality, morbidity, hospital charge, and length of stay, and their incidence can be predicted by several factors.