Background: We aimed to compare the oncologic outcomes of intracorporeal urinary diversion (ICUD) and extracorporeal urinary diversion (ECUD) following robot-assisted radical cystectomy (RARC) in patients diagnosed with bladder cancer. Materials and Methods: Medical records of 730 patients who underwent RARC between April 2007 and May 2019 in 11 tertiary referral centers were retrospectively reviewed. We assessed recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS) in the two groups using the Kaplan-Meier method. Cox regression models were used to identify factors associated with RFS, CSS, and OS. Results: Among 591 patients, neobladder diversion was performed more frequently in the ICUD group (70.8% vs 52.5%, p = 0.001). The median follow-up duration was shorter in the ICUD group than in the ECUD group (16 vs 26 months, p < 0.001). The rates of overall recurrence (36.5% vs 25.5%, p = 0.013) and pelvic recurrence (12.1% vs 5.9%, p = 0.031) were higher in the ECUD group. However, no differences in 5-year RFS (43.2% vs 58.4%, p = 0.516), CSS (79.3% vs 89.7%, p = 0.392), and OS (74.3% vs 81.4%, p = 0.411) were noted between the two groups. Multivariable analysis revealed that when compared to ICUD, ECUD was not associated with RFS (hazard ratio [HR], 0.982; p = 0.920), CSS (HR, 0.568; p = 0.126), and OS (HR, 0.642; p = 0.124). Conclusion: Although there was a difference in recurrence rate between the two groups, multivariable analysis indicated that the diversion technique after RARC did not affect the oncologic outcomes. Large prospective studies with long-term follow-up are warranted to verify the oncologic outcomes of ICUD and ECUD following RARC.