在复杂自由曲面类零件的加工过程中，粗加工往往要占去大部分的时间。本文从提高加工稳定性及加工效率的角度出发，提出了一个复杂多曲面数控粗加工的算法，即采用分层切削法，通过平面／曲面求交技术和交线环的等距、自交、集合等基本运算，按“端点同环最短距离优先剖面线算法”规划每一切削层的刀具轨迹。最后给出了编程应用实例。 In the processing of complex freeform surface parts, rough machining often takes up most of the time. In this paper, from the perspective of improving machining stability and machining efficiency, a complex multi-surface NC roughing algorithm is proposed, that is, using the hierarchical cutting method, through plane / surface intersection technology and intersecting ring isometric, self- Set and other basic operations, according to “the end of the ring with the shortest distance priority hatching algorithm” planning tool path for each cutting layer. Finally, the programming application examples are given.