This　study　analyzes　the　effect　of　shot　peening　on　the　surface　integrity　of　nickel-based　single　crystal　su-peralloys　(SX)　and　the　evolution　of　stress　concentration　factors　caused　by　surface　finishing　and　casting　micropores　near　the　surface　before　and　after　shot　peening　by　numerical　simulation.　On　one　hand,　SX　forms　a　surface　gradient　plastic　deformation　structure　after　shot　peening.　The　surface　yield　strength　is　82%　higher　than　that　of　the　matrix　by　nanoindentation　fitting.　The　deformation　of　the　surrounding　materials　of　the　near-surface　casting　micropores　is　significantly　greater　than　that　of　the　materials　at　the　same　depth　by　EBSD.　On　the　other　hand,　the　series　parameters　of　surface　roughness　after　shot　peening　are　higher　than　those　of　grinding.　However,　the　stress　concentration　Kt1.32　at　the　bottom　of　the　smooth　crater　is　sig-nificantly　lower　than　that　of　grinding　＂furrow＂　Kt1.94.　The　surface　gradient　deformation　caused　by　shot　peening　flattens　the　surface　casting　micropores　so　that　the　stress　concentration　at　the　upper　end　of　the　micropores　is　significantly　smaller　than　that　in　the　grinding　state.　Based　on　the　above　two　effects,　the　rotary　bending　fatigue　limit　of　the　single　crystal　alloy　after　shot　peening　at　650　degrees　C　is　increased　by　13.0%　compared　with　the　ground　state.　The　peened　sample　no　longer　originates　from　the　casting　micropores.(c)　2022　Elsevier　B.V.　All　rights　reserved.