It is fit for the prostate electrolytic therapeutic apparatus for treating BOO bladder outflow obstruction syndrome caused by prostate disease. It is made up of tube, conical connector, ball sacculus, guiding tip, diagnosis electrode and inner electrode. The tube is made of medical silicone gel. It is entered bladder through the urethra and fixed by location sacculus in the bladder, the diagnosis eletrode is in the prostate. Eight models: 16Fr/ 2.0, 16Fr/2.5, 16 Fr/ 3.0, 16Fr/3.5, 16Fr/4.0, 16 Fr/4.5, 16Fr/5.0, 16Fr/5.5.