Abstract: Carbon fiber reinforced plastics has been widely used in the high level equipment of aerospace area. During edge milling, the tool wear is fast, and it is easy to form burr, delamination, edge collapse and other defects. Burrs on the edge are the uppermost imperfect, causing lots of manual work. Researching the means of burr inhibition is important for the enterprises therefor. Through analyzing the mechanism of burr formation in milling of CFRP, a new cutter is designed with optimized structure. The new cutter has four group of cutting areas, they are pineapple right helix cutting edges, normal right helix cutting edges, pineapple left helix cutting edges and normal left helix cutting edges. The trimming tests of CFRP are performed by the new cutter,the pineapple milling cutter and the cross-flute cutter. The results show that the edge burrs are suppressed effectively by the new cutter.