In　order　to　show　the　thermal　performance　of　spindle　by　rule　and　line,　firstly,　this　paper　presents　a　three-dimensional　finite　element　analysis　model　for　thermal　analysis　of　high　speed　spindle;　Then　by　studying　the　heat　generation　and　radiation　mechanism　of　the　spindle,　temperature　distribution　has　been　analyzed　accurately　and　intuitively　under　the　heat-stable　condition　based　on　the　three-dimensional　model;　Finally　effective　actions　have　been　proposed　to　improve　the　condition　of　the　spindle＇s　heat　generation,　and　thus　can　guarantee　the　highly　effective　characteristic　of　the　spindle　in　machining　process.