Parameterization design was applied to actuator structural design and three-dimensional entity modeling of brake by wire system. Based on pro-engineering software environment, motor driving entity model of brake by wire system was established. Motion transformation device, force booster device, cylindrical gear decelerate device were included. According to relative motor parameters and structural function of the equation, structural design of motion transformation device, force booster device and cylindrical gear decelerate device were carried on. Under Pro-E entity modeling platform, three-dimensional entity model of brake by wire system was established.