Prostate cancer is the most common cancer in elderly males in western country. It is also a major health concern, especially in China with its greater proportion of elderly men in the general population. Currently, radical prostatectomy(RP) is the mainstream treatment for localized PCa to show a benefit for cancer-specific survival (CSS). However, the patient who underwent RP might suffer from the complication of erectile dysfunction or urinary incontinence. In 2004, a new method using steep pulses to treat tumor was appeared. It showed that steep pulses could bring about Irreversible Electroporation (IRE) of cell, leading tonecrosis of tumor cells. And it seemed to do no harms to the nerve and Vascular epithelial cell. The device of steep pulse had already been approved by FDA in 2011.However, this device of steep pulse has disadvantages like: (1)sever muscle contraction;(2)Urethral injury; (3)Capsule injury;(4)Nerve degeneration. This new device which is called Composite Steep-pulse Treatment Apparatus, may have the potential to conquer these disadvantages.