Aiming at the problem of burrs and other processing defects on the surface of carbon fiber composites finishing machining,a end mill with new four-edge coarse and fine interlaced edge structure and the conventional cemented carbide end mill were selected.Under the same conditions,high-speed milling experiments were performed on carbon fiber composites with different fiber direction angles θ=45°,90°,135°.By comparing the processed surface burr,milling axial force,surface roughness,surface micro-morphology and burr suppression mechanism,it is concluded that when the new type of coarse and fine interlaced end mills are milled,the burrs on the processed surface are both significant in length and quantity; the average value of the milling force Fz of the three fiber materials decrease by 20.93%,17.74% and 5.78%; the surface roughness of the work-piece is relatively small when the fiber direction angle θ is 45° and 90°，and the surface quality is relatively good; the surface roughness of the work-piece with the fiber direction angle θ=135° increases sharply,and the processing quality is far beyond the qualified standard.In general,due to its staggered distribution structure，the new type of coarse and fine staggered end mills can effectively suppress the generation of burrs,and ensure that the surface roughness does not change drastically， so it is more suitable for the milling of carbon fiber composites.