The authors produced a special urethral catheter with two carbon fiber electrodes to carry out electromyography of the detrusor bladder. Carbon fiber electrodes have been found to be superior to metal electrodes as surface electrodes in physiological fluid. Subjects were 20 adults; 2 cases are shown in this paper. The results of the experiment demonstrate that it is possible to carry out electromyography of the detrusor bladder in good condition with diminished noise level. This method allows a more accurate, neurophysiological evaluation of the vesical function, as compared with traditional methods.