High-speed　cutting　is　an　important　method　for　improving　the　efficiency　and　quality　of　machining　mold　steel,　but　the　wear　of　tool　is　one　of　the　key　factors　restricting　the　improvement　of　cutting　speed,　which　brings　higher　requirement　for　the　material　of　tools.　At　present,　most　of　the　research　is　about　high-speed　cutting　for　high　hardness　mold　steel,　while　only　a　limited　research　work　on　the　pre-hardened　plastic　mold　steel　with　hardness　between　30　HRC　and　42HRC,　such　as　P20　mold　steel.　To　explore　the　effects　of　cutting　speed　on　the　wear　properties　of　TiAlN　PVD　coated　tool　for　cutting　P20　mold　steel,　the　experiments　in　different　cutting　speeds　were　carried　out　under　dry　condition.　Wear　characterization　of　the　rake　and　the　flank　surfaces　were　investigated　by　using　scanning　electron　microscopy　(SEM)　and　energy　dispersive　X-ray　analysis　(EDX).　It　was　revealed　that　at　the　low　speed　(160m/min),　adhesion　(built-up　edge)　followed　by　delamination　was　found　to　be　the　cause　of　wear　damage;　at　the　high　speed　(320m/min),　the　dominant　wear　mechanisms　were　oxidation　wear　and　diffusion　wear,　followed　by　adhesive　wear　and　melt　wear;　as　the　cutting　speed　increased,　the　proportion　of　oxidation　wear　and　diffusion　wear　was　gradually　increased.　©　(2014)　Trans　Tech　Publications,　Switzerland.