Abstract: In this paper we study the way of reducing the back-play time in scanning process for optimizing the scanning path planning. Genetic algorithm (GA) is suitable to solve the optimization of complex problems such as group technology, reliability design, vehicle path selection and scheduling, transport, et al. Thus GA is utilized to settle the problem, based on the comparison between the optimization of scanning path and the optimization of traveling salesman problem (TSR). The features of scanning path are considered in achieving the method thoroughly including chromosome code, fitness function, cross operator, variation operator, choice way, control parameters, terminal condition and so on. The method can find optimized path and shorten the back-play time in scanning path. So it can improve efficiency and forming quality of RP system.