Carbon fiber reinforced polymer (CFRP) has the characteristics of multi-scale and multi-equal structure, showing significant anisotropy and heterogeneity, poor machining performance, and easy to appear obvious burrs and delamination. In order to analyze the characteristics in helical milling of CFRP, the ball helical milling of CFRP was studied, and cutting forces, tool wear and hole-making quality were analyzed in detail. First, based on the result of the experiment, the changes of axial and radial cutting force and cutting temperature over cutting parameters were analyzed.  Then, tool wear was studied respectively from the lateral edge and spherical edge. Finally, hole diameter was analyzed from the perspective of the hole deep, entry and exit hole-making quality, and delamination factor was used to describe entry delamination state. The results show that the ball end milling cutter has better cutting characteristics in the ball helical milling of CFRP, but hole-making quality needs to be improved.