The　pseudo-static　tests　and　extended　parameter　analyses　on　the　Reinforced　Concrete　(RC)　pile-soil　interaction　considering　slope　effect　were　carried　out　to　study　the　effect　of　slope　on　pile-soil　interaction　in　integral　abutment　jointless　bridges.　The　influence　of　the　slope　effect　on　the　mechanical　behaviors　of　RC　pile-soil　system　is　discussed.　The　results　reveal　that　the　hysteresis　curve　at　slope　side　exhibits　less　plumpness　compared　to　the　opposite　side　of　the　slope.　This　plumpness　decreases　with　decreasing　distances　from　pile　side　to　slope　crest,　leading　to　a　gradual　reduction　in　pile-soil　interaction.　When　the　distance　from　pile　side　to　slope　crest　decreases　from　2　times　pile　diameter　to　0　and　2　times　pile　diameter　from　slope　crest　to　pile　side,　the　maximum　horizontal　forces　of　pile　head　at　slope　side　decrease　by　15.0%　and　28.　6%,　respectively.　Moreover,　the　maximum　soil　resistances　surrounding　the　pile　decrease　by　18.　2%　and　26.　6%,　and　the　maximum　bending　moments　of　the　pile　decrease　by　8.0%　and　16.9%,　respectively.　When　the　distance　from　pile　side　to　slope　crest　is　2　times　pile　diameter　and　the　slope　angle　is　less　than　20　or　the　distance　exceeds　4　times　pile　diameter,　the　influences　of　the　distance　and　slope　angle　on　the　mechanical　behaviors　of　pile-soil　system　are　minimal.　In　such　cases,　the　slope　effect　can　be　neglected　in　the　design　of　pile.　The　mechanical　behaviors　of　pile-soil　system　remain　unaffected　when　the　pile　displaces　towards　the　opposite　side　of　the　slope.　However,　the　friction　angle　of　the　slope　soil　has　a　significant　impact　on　the　mechanical　behaviors　of　pile-soil　system.　Consequently,　clay　with　a　smaller　friction　angle　should　be　preferred　in　engineering.　©　2023　Southeast　University.　All　rights　reserved.