A　new　idea　for　3D　thermal　model　was　proposed　for　the　whole　stator　of　totally　enclosed　fan　cooled　asynchronous　motor.　The　model　was　built　based　on　thermal　dissipation　coefficients　method　which　incorporates　the　theoretical　analysis　and　measuring　data　to　deal　with　the　complex　thermal　exchange　between　the　windings　and　slot　insulation　reasonably.　A　finite　element　method　(FEM)　modeling　of　end　windings　was　also　built.　Based　on　the　model,　steady-state　thermal　field　and　the　highest　temperature　variation　of　the　stator　under　rated　load　were　calculated,　and　the　experiments　verified　the　model　effectively.　The　model　provides　the　important　criteria　for　accurate　motor　thermal　protection,　and　also　lays　the　foundation　for　3D　thermal　modeling　of　the　motor　including　stator　and　rotator.　©　2010　Chinese　Society　for　Electrical　Engineering.