High　speed　cutting　is　an　important　means　to　improve　the　efficiency　and　the　quality　of　machining　mold　steel,　but　the　tool　wear　is　one　of　the　key　factors　restricting　the　increase　of　the　cutting　speed,　leading　to　higher　requirements　for　cutting　tool　materials.　At　present　the　researches　of　high-speed　cutting　of　mold　steel　are　mainly　on　the　hardness　mold　steel,　but　less　on　P20　mold　steel　which　hardness　is　30-42HRC.　This　paper　mainly　studies　the　effect　of　cutting　speed　on　wear　property　of　TiAlN　PVD　coated　tools　when　high-speed　milling　of　P20　mold　steels.　The　experiment　was　conducted　using　two　different　high　cutting　speeds　under　dry　condition,　320m/min　and　500m/min.　Wear　characterization　of　the　rake　and　the　flank　surfaces　as　well　as　the　collected　chips　were　performed　using　scanning　electron　microscopy　(SEM)　and　energy　dispersive　X-ray　analysis　(EDX).　It　was　found　that　at　high　speeds,　the　dominant　wear　mechanisms　were　oxidation　wear　and　diffusion　wear,　followed　by　adhesive　wear　and　melt　wear;　as　the　cutting　speed　increased,　the　wear　surface　area　of　rake　face　will　be　closer　to　the　main　cutting　edge.　©　(2014)　Trans　Tech　Publications,　Switzerland.