In　order　to　improve　the　modeling　accuracy　of　the　motorized　spindle,　a　comprehensive　thermal　contact　resistance　(TCR)　modeling　method　was　proposed.　The　fractal　theory　was　introduced　to　calculate　the　joint　thermal　contact　resistance.　The　W-M　function　and　the　M-B　fractal　model　were　established　to　characterize　the　microscopic　contour　of　the　rough　surface.　The　bulk　thermal　resistance,　constrained　thermal　resistance,　micro-gap　thermal　resistance　and　overall　thermal　contact　resistance　of　the　rough　surface　of　different　materials　were　discussed.　The　finite　element　method(FEM)　was　used　to　establish　the　multi-physics　coupling　analysis　model　of　the　motorized　spindle,　adding　the　theoretical　calculation　of　thermal　contact　resistance　in　the　joint　surface　of　the　motorized　spindle.　The　temperature　rise　and　deformation　variation　of　the　motorized　spindle　were　simulated　under　the　condition　of　thermal　contact　resistance.　The　simulation　results　demonstrate　the　influence　of　thermal　contact　resistance　on　the　temperature　and　thermal　deformation　of　the　motorized　spindle.　The　results　show　that　when　the　thermal　resistance　of　the　high-speed　motorized　spindle　is　considered,　the　temperature　rises　and　the　deformation　increases,　and　the　accuracy　of　the　model　is　more　accurate,　which　is　closer　to　the　actual　processing.