To research and design a type of implantable functional electrical stimulator for restoring the injured peripheral nervous system. The crucial circuits of the implantable neural prosthesis were designed based on the digital signal processor TMS320VC54x and programmable logic device XC95144XL, corresponding program were developed and an experiment was carried on for verifying the system. Results show that the prototype realized the bi-directional wireless communication between the implantable simulator and the external controller. The output of stimulation pulse width, duration and some other parameters are controllable. This low power and system integrated implantable neural prosthesis stimulator could generate biphasic stimulating pulses, which after improving and optimizing could be used for repairing injured nerve system.