Between October 1988 and November 1990, 39 adult patients (average age 18.5 years) with enuresis underwent urodynamic evaluation. Filling cystometry was performed transurethrally using normal saline in the supine position. Abnormal cystometric findings were observed in 11 patients (28.2%), unstable bladder being the most common pathology (n = 7). Abnormal cystometric findings did not correlate with sex, age and diurnal symptoms of the patients. The only difference between pathologic and normal cystometry groups was the functional bladder capacity which is found to be reduced significantly in the former group. Cystometry does not contribute to the diagnosis of enuresis but helps to enlighten its physiopathology.