Tool path planning is an important content in the process of complex surface CNC machining,and tool path optimization can significantly improve the machining efficiency,reduce the energy consumption of machine tools. Based on the description of the tool path optimization and the analysis of impact factors,an optimization model is established to achieve high machining efficiency and low energy consumption,with the constraints of the spindle speed,feed rate,power of machine tool,spindle torque,machining intervals and surface quality. In the optimization process,the number of the cutting contact points is determined by the optimized the cutter spacing and intervals,according to the surface curvature,cutter radius,and residual height of surface. The connection order and path way are optimized by using adaptive simulated annealing genetic algorithm. Finally,the validity and practicability of the proposed method are verified by practical examples compared with several traditional methods.