Abstract: In CNC machining for the parts with sculptured surfaces,NURBS tool paths generation needs to segment a large number of ordered cutter location points so as to select the points for NURBS fitting.The quality of segmentation plays a key impact on NURBS tool path generation.By analyzing the property of the NURBS tool path,the boundary points and the connection of the tool paths are classified.A segmentation approach is proposed by using hierarchical clustering algorithm.According to the segmenting result,the points fitted with the NURBS curve can be determined by justifying the type of the boundary points.The case study showed that the new algorithm is robust,effective and highly adaptable to the different surfaces and curves.