The　contact　between　substrate　and　micro-cantilever　simplified　as　an　ideal　flat　substrate　contact　with　a　micro-cantilever　rough　surface.　A　three-dimensional　adhesive　contact　model　was　established　on　isotropic　rough　surfaces　exhibiting　fractal　behavior,　and　the　equivalent　plastic　strain　was　discussed　using　the　finite　element　analysis.　The　maximum　equivalent　plastic　strain　and　its　depth　were　presented　with　the　different　paths　of　rough　solid　when　loading.　The　result　show　that　the　equivalent　plastic　strain　versus　different　depth　which　at　different　locations　showed　different　laws,　in　the　top　area　of　the　asperities　versus　different　depth,　the　maximum　equivalent　plastic　strain　occurs　in　the　subsurface　range　about　0.5　mu　m　from　the　surface　or　on　the　surface.　In　addition,　with　different　deformation　characteristics,　the　degree　of　the　equivalent　plastic　strain　was　different.　The　contact　model　between　micro-cantilever　rough　surface　and　flat　substrate　will　lay　a　foundation　to　further　research　on　the　substance　of　the　process　of　friction　and　wear.