We examined the relationship between cerebral magnetic resonance imaging (MRI) findings and urinary dysfunction in 70 consecutive patients with definite multiple sclerosis. MRI-weighted lesion scores for seven different brain regions were recorded according to the number and size of cerebral lesions. Thirty-two subjects (46%) had urinary symptoms and 38 (54%) were asymptomatic. Subjects with urinary symptoms exhibited greater overall functional disability and a higher midbrain MRI-weighted lesion score than asymptomatic patients. No statistically significant group differences were found for the other brain regions.