A　thermo-mechanical　coupling　model　for　a　rigid　flat　plane　and　an　elastic-plastic　rough　surface　based　on　three-dimensional　fractal　theory　is　established.　The　model　considers　the　interaction　between　asperities,　and　integrates　the　heat　flux　coupling　on　the　contact　interface.　To　obtain　the　transient　stress/temperature　distribution　of　the　rough　solid,　the　thermo-mechanical　problem　under　this　3D　model　is　solved　by　using　the　nonlinear　multiphysics　field　of　the　ANSYS　software.　The　numerical　results　from　the　analysis　and　simulation　show　that　the　maximum　contact　temperature　of　the　rough　surface　increases　quickly　in　the　initial　sliding　due　to　the　velocity　mutation,　but　the　temperature　rises　slowly　during　the　constant　sliding　process.　The　results　also　show　that　the　VonMises　equivalent　stress　distribution　of　the　rough　surface　is　very　uneven.　And　a　tension　stress　zone　exists　at　a　certain　depth　from　the　contact　surface　in　the　rear　of　the　contact　asperity.　The　results　demonstrate　that　the　VonMises　equivalent　stress　of　the　contact　surface,　the　maximum　tensile　stress　and　the　layer　thickness　of　the　tensile　stress　increase　obviously　in　transient　sliding　contact　and　forming　of　instantaneous　flash　temperature.　These　results　provide　a　theoretical　basis　for　crack　initiation　and　propagation.　©　2011　Journal　of　Mechanical　Engineering.