In　this　work,　the　high　temperature　wear　behavior　of　Ca-Ti　modified　high-boron　high-speed　steel　is　investigated.　The　results　indicate　that　the　microstructure　of　the　alloy　consists　of　matrix　and　eutectic　borocarbide.　Ca-Ti　modification　aims　at　improving　the　stability　of　borocarbide　under　wear　condition　through　making　the　distribution　of　borocarbide　more　isolated.　The　wear　experiment　revealed　that　the　wear　resistance　of　high-boron　high-speed　steel　is　much　better　than　that　of　T15　steel　due　to　the　better　oxidization　resistance　and　mechanical　property　of　matrix　and　borocarbide　respectively.　Under　25　degrees　C　and　200　degrees　C,　main　wear　mechanism　of　high-boron　high-speed　steel　is　adhesive　spalling.　When　the　temperature　is　400　degrees　C,　the　mechanism　becomes　combination　of　adhesive　spalling　and　oxidization.　Under　600　degrees　C,　the　mechanism　is　oxidation.