Orthotopic bladder substitution is one of the real advances in modern Urology. in this work we evaluate the most commonly used type, Y shaped, Camey II, W shaped ileal neobladder, clinically, radiological ,and urodynamically. The study was done on 21 male patients with radical cystoprostatectomy and ileal neobladder substitution. The results proved the efficacy of Y shaped ileal neobladder and the best segment to be used is the ileal segment as it protects the upper tract as it has lowest pressure by proved urodynamically large volume, perfect compliance less residual urine.