Background: bladder cancer is common among genitourinary tract. Radical cystectomy with urinary diversion is the widely accepted treatment. However, no consensus exists regarding the best orthotopic neobladder creation intestinal segment. Aim of the work: to evaluate functional and oncological outcome of ileal and sigmoid orthotopic urinary diversion.  Patients and methods: The study included two groups of 40 patients in each group (ileal and sigmoid groups). Each group was further divided in two twenty subgroups; prospective and retrospective. Ileal group operated in Urology and Nephrology centre (UNC) and Al-Azhar University hospital (Damietta), while patients in sigmoid group were operated in Al-Azhar University hospital (Cairo). All underwent full history taking, clinical examination, and laboratory investigations. Then, postoperatively, all were followed up for 6 months. In each postoperative follow up visit, patients were assessed clinical, radiological, urodynamic study and by laboratory investigations and patients' quality of life were evaluated.  Results: In ileal orthotopic diversion, early postoperative complications were bleeding (2.5%), urine leakage (2.5%) and wound infection (25%). Diurnal continence was achieved in 90%, while nocturnal continence was achieved in 70%. The early postoperative complications were urine leakage (2.5%), obstruction (2.5%), and ileus (12.5%). The late complications were DVT (2.5%) and intestinal obstruction (5.0%). In addition, 2.5% were died from disease. Tumor recurrence was pelvic in 7.5%, distant (hepatic) in 2.5%. Only 25% of patients were potent and urine culture revealed E-coli in 40.0%. In the sigmoid orthotopic diversion group, the early postoperative complications were urine leakage (17.5%), obstruction (2.5%), ileus (7.5%), bleeding (2.5%), DVT (2.5%) and faecal leak (2.5%). Late complications were pouch stones (10.0%), stricture urethra (12.5%), ureterocolic stricture (7.5%), pouch stones plus stricture urethra in 5.0%, DVT (2.5%), intestinal obstruction (10.0%) and hematemesis in 2.5%. In addition, 12.5% were died. Tumor recurrence was pelvic in 25.0%. Only 7.5% of patients were potent and urine culture revealed E-coli in 35.0%. Diurnal continence was reported in 92.5%, while nocturnal continence was reported in 60%. Conclusion: both sigmoid and ileal orthotopic neobladder provided a satisfactory outcome. Sigmoid neobladder was associated with lower rate of complications and better functional outcome. However, there were many late-term complications detected in this group.