Micturitional histories were taken from 39 patients with acute brainstem stroke. Within 3 months from onset, 49% had irritative as well as obstructive urinary symptoms, the most common being voiding difficulty and nocturnal urinary frequency in 28%, followed by urinary retention in 21%. Urodynamic studies of 11 symptomatic patients revealed detrusor hyperreflexia in 73%, low compliance bladder in 9%, atonic cystometrogram in 27%, detrusor-sphincter dyssynergia in 45% and uninhibited sphincter relaxation in 27%. Three asymptomatic patients had normal urodynamic findings. Brain magnetic resonance images of the lesions of the symptomatic patients were concentrated in the dorsolateral pons including pontine reticular nucleus and the reticular formation adjacent to the medial parabrachial nucleus and the locus coeruleus. These regions seem to be mainly responsible for supranuclear types of pelvic and pudendal nerve dysfunction in our patients with brainstem stroke, corresponding to the pontine urinary storage and micturation center reported in animal studies.