The　effect　of　pre-deformation　induced　by　the　tensile　fracture　at　room　temperature　on　the　microstructure　evolution　of　Ni-Al　model　single　crystal　superalloy　during　thermal　exposure　at　1000　degrees　C,　was　investigated　by　scanning　electron　microscope　and　transmission　electron　microscopy.　Recrystallization　occurs　near　the　fracture　surface　where　the　most　severe　plastic　deformation　was　suffered.　The　average　size　of　recrystallization　grains　in　front　of　the　recrystallization　area　is　much　larger　than　that　of　at　the　fracture　surface.　Far　from　the　fracture　surface,　the　average　size　of　coarsened　gamma＇　precipitates　in　the　slip　bands　is　larger　than　that　of　out　of　the　slip　bands.