The　study　of　the　instantaneous　frictional　temperature,　stress,　and　equivalent　plastic　strain　generated　when　two　surfaces　are　in　frictional　sliding　process　plays　a　significant　role　in　understanding　friction　and　wear　mechanism.　A　thermomechanical　coupling　model　between　a　rough　body　and　a　flat　body　is　established.　The　model　integrates　the　heat　flux　coupling　between　the　sliding　surfaces　and　considers　the　effects　of　the　interaction　among　contact　asperities　and　elastoplastic　deformation　of　the　rough　body.　The　thermomechanical　problem　under　this　three-dimensional　model　is　solved　by　the　nonlinear　finite　element　methods　in　ABAQUS　software.　The　results　show　that　the　temperature,　contact　pressure,　and　stress　are　coupled.　The　results　of　the　real　contact　area　and　the　instantaneous　frictional　temperature,　contact　pressure,　and　VonMises　equivalent　stress　on　the　local　contact　region　fluctuate　obviously　due　to　the　interaction　among　the　adjacent　contact　asperities.　The　influence　of　asperity　interaction　is　not　constant　but　intermittent.　Its　time　interval　is　related　to　the　added　interaction　of　a　new　adjacent　contact　asperity.　The　fluctuation　of　the　VonMises　equivalent　stress　makes　the　equivalent　plastic　strain　of　the　frictional　surface　layer　accumulate　continually　which　might　cause　fatigue　wear　and　plastic　deformation　wear　of　the　material　when　the　frictional　rotating　process　was　repeated.