Additive　manufacturing　as　a　new　manufacturing　technology　has　significant　advantages　in　producing　complex　impeller　parts,　but　the　surface　roughness　limits　its　wide　application.　Therefore,　the　work　aims　to　solve　the　problem　of　excessive　surface　roughness　of　TC4　titanium　alloy　(Ti6Al4V)　impeller　parts　produced　by　additive　manufacturing.　In　order　to　improve　the　surface　roughness　of　through-hole　or　complex　outer　surface　parts　caused　by　powder　adhesion　and　spheroidization　defects,　abrasive　flow　polishing　technology　was　applied　to　polish　the　surface　of　TC4　titanium　alloy　specimens.　The　effect　of　abrasive　flow　polishing　on　the　surface　roughness　and　morphology　of　TC4　titanium　alloy　was　studied　under　different　abrasive　particle　size,　working　pressure　and　processing　time.　The　polishing　process　of　abrasive　was　simulated　by　Fluent　software　to　explore　the　mechanism　of　abrasive　particles　on　the　static　pressure,　dynamic　pressure,　turbulent　kinetic　energy　and　turbulence　intensity　near　the　wall.　A　three-dimensional　impeller　model　was　built　and　the　actual　processing　conditions　were　taken　as　simulation　parameters　to　verify　the　effectiveness　of　abrasive　flow　polishing　method.　At　the　same　time,　wear　resistance　of　the　TC4　titanium　alloy　before　and　after　abrasive　flow　polishing　were　tested　and　analyzed.　The　TC4　titanium　alloy　specimens　produced　by　additive　manufacturing　were　cut　into　40　mm×40　mm×5　mm　by　wire　cutting,　cleaned　and　dried.　The　SMK-600　abrasive　flow　polishing　machine　was　used　to　optimize　the　surface　roughness　of　titanium　alloy　specimens　by　cutting　the　workpiece　surface　through　the　reciprocating　movement　of　abrasive　media.　The　solid　particles　of　abrasive　medium　were　SiC　abrasive　particles,　and　the　mixture　of　methyl　silicone　oil　and　polyacrylamide　was　used　as　liquid　medium.　Experiments　verified　that　titanium　alloy　parts　with　surface　roughness　Ra　©　2023　Chongqing　Wujiu　Periodicals　Press.　All　rights　reserved.