Bladder dysfunction is one of the major symptomatologies characteristic to HAM (HTLV-I associated myelopathy). Four patients, 3 females and 1 male, were diagnosed by neurologists to have HAM with spastic gait disturbance and increased titer of antibody to HTLV-I. They complained of urge incontinence, bed wetting, difficulty in micturition and/or pollakisuria. Urodynamically, in 3 of them severe uninhibited detrusor contractions were observed. On the other hand, in one case detrusor contractility was lost completely at voiding. In all patients, bladder sensation was well preserved. Corticosteroids and interferon could not improve their urological symptoms. Clean intermittent catheterization (CIC) put on 3 patients who had a significant amount of residue relieved them of urinary incontinence. We believe that HAM in patients suffering from severe difficulty in micturition is a good indication for CIC.