The aluminum base microwave printed circuit board has the wide application foreground in high-tech fields. But the insulating layer of PCB is a difficult-to-machining material. In this paper, the experimental research on the wear mechanics and cutting coating comparison in high speed milling of the Rogers 6002 micro wave PCB. TiN and TiAlN coated cemented carbide cutting tool are select to milling the micro wave PCB. The effect of milling parameters and cutting length on cutting force is investigated. SEM is used to observe the wear morphology of the flank face of cutting tools. Research results show the wear mechanisms of coated tool include abrasive wear and adhesive wear. TiAlN coating is more suitable for high milling the insulating layer of microwave PCB because of its high hardness and wear resistance. The research results are contributive to choose proper high-speed cutting tools and parameters.