Using a urodynamic technique, vesicourethral function was evaluated in 30 patients who had undergone surgery for uterine cancer. In all 28 patients treated with radical hysterectomy, detrusor function was damaged irrespective of the use of the Cavitron ultrasonic surgical aspirator (CUSA), whereas, in 2 patients treated with semiradical hysterectomy, the function was preserved. Vesicourethral functions 3 weeks after the operation in all 28 patients treated with radical hysterectomy showed underactive detrusor function with low compliance. In 10 out of these 28 patients, postoperative maximum urethral closure pressure (MUCP) did not decrease, without relation to the use of CUSA nor to the presence of detrusor sphincter dyssynergia, and more than 5 weeks were required to reduce residual urine to less than 50 ml. On the other hand, in the remaining 18 patients, postoperative MUCP decreased, and residual urine decreased to less than 50 ml by 5 weeks after the operation. From the results obtained here, we can conclude that the evaluation of MUCP at an early phase after the operation is a useful tool to predict complications caused by residual urine, such as urinary tract infection, irreversible alteration of detrusor function or deterioration in renal function.