Urodynamic evaluation in pediatric neurogenic bladder is prerequisite for accurate prediction of prognosis and selection of appropriate treatment modality. We classified normal, hyperreflexic and areflexic bladders by cystometry. Hyperreflexic bladder was subdivided into two groups with or without detrusor sphincter dyssynergia and areflexic bladder into low pressure and high pressure. Among 36 patients with myelodysplasia on whom we performed a videourodynamic study vesicoureteral reflux was found in three of 7 patients with hyperreflexia with detrusor sphincter dyssynergia, two of 6 patients with hyperreflexia without detrusor sphincter dyssynergia and five of 10 patients with areflexia with high pressure. Low pressure areflexic bladder didn't show vesicoureteral reflux. When we evaluated 39 pediatric neurogenic bladder patients with a mean 25.5 follow-up months period, upper tract deterioration was improved and normal findings persisted in all the compliant patients to treatment. In the noncompliant group initial abnormal upper tract findings persisted or aggravated, especially in hyperreflexic bladder with dyssynergia and high pressure areflexic bladder. One of the three hyperreflexic bladders with dyssynergia and two of six high pressure areflexic bladders received augmented cystoplasty. These data show that urodynamic evaluation in pediatric neurogenic bladder provides excellent criteria for selecting high risk groups in pediatric neurogenic bladder.