OBJECTIVES: To evaluate the risk factors for postoperative ileus in patients who underwent robot-assisted radical cystectomy with intracorporeal urinary diversion. METHODS: We retrospectively analyzed 78 patients with bladder cancer who underwent robot-assisted radical cystectomy with intracorporeal urinary diversion at Fujita Health University between 2011 and 2021. Baseline characteristics and perioperative outcomes were compared between the cohorts with and without ileus. Logistic regression analysis was used to identify the risk factors for postoperative ileus. RESULTS: Out of the 78 patients included in this study, 20 (25.6%) developed postoperative ileus. The ileus cohort was associated with a significantly lower Geriatric-8 score (P = 0.003) and a higher rate of previous abdominal/pelvic surgery (P = 0.04) compared with those of the nonileus cohort. Significantly longer intestinal tract reconstruction time, hospital stay, time to mobilization, fluid intake, solid intake, flatus, and stool were observed in the ileus cohort. According to the results of the logistic regression analysis, the Geriatric-8 sum (P = 0.009), time to mobilization (P = 0.03), and time to fluid intake (P = 0.004) were independent predictors of postoperative ileus. In the model predicting postoperative ileus, the area under the receiver operating characteristic curve was 0.716, and the cutoff value of the Geriatric-8 sum was 13. CONCLUSIONS: Early mobilization and fluid intake and low Geriatric-8 scores were significant risk factors for postoperative ileus. Preoperative Geriatric-8 evaluation is a useful tool for predicting postoperative ileus. Comprehensive enhanced recovery after surgery, including key components, may help bowel recovery and prevent subsequent ileus.