The Pneumatic Braking Energy Recovery Systems is energy recovery systems that converts the consumed kinetic energy while braking the car into the auxiliary power while restarting the car.It mainly consists of the energy recovery part and energy use part.The energy recovery part achieved by converting the mechanical energy into the potential energy in the form of the compressed air.It'll be a break to the car of energy saving and a new conception to use of the enormous energy when braking the car which has always been ignored.