A　centrifugal　compressor　with　rotational　speed　60　000　r/min　is　designed　according　to　150　kW　class　supercritical　carbon　dioxide　(SCO2)　simple　Brayton　cycle.　The　accuracy　of　the　physical　property　tables　of　SCO2　significantly　affect　the　stability　and　accuracy　of　SCO2　compressor　aerodynamic　performance　predictions　due　to　the　dramatic　variation　of　the　physical　properties　of　SCO2　near　the　critical　point.　A　400×400　precision　physical　property　table　is　able　to　lead　to　a　reliable　SCO2　compressor　aerodynamic　performance.　The　aerodynamic　performances　of　the　designed　SCO2　centrifugal　compressor　in　designed　and　off-designed　conditions　are　numerically　evaluated　with　the　three-dimensional　Reynolds-averaged　Navier-Stokes　(RANS)　and　k-Ε　turbulence　model.　The　centrifugal　impeller　tip　leakage　flow　is　also　analyzed　in　detail.　The　numerical　results　show　that　the　aerodynamic　efficiency　of　the　designed　SCO2　centrifugal　compressor　reaches　73.2%　and　the　pressure　ratio　gets　2.207　under　the　designed　condition　in　consideration　of　the　impeller　tip　leakage　flow　loss.　The　good　performance　of　the　SCO2　centrifugal　compressor　in　off-designed　conditions　is　verified.　The　aerodynamic　efficiency　of　the　SCO2　centrifugal　compressor　in　consideration　of　the　impeller　tip　leakage　flow　loss　decreases　by　14.0%　compared　with　the　case　without　impeller　tip　leakage　flow　effect.　Three　regions　of　the　impeller　tip　leakage　flow　field,　i.e.　the　separation　flow　region　along　the　mainstream　flow　direction,　the　backflow　region　of　the　upper　part　in　tip　clearance　affected　by　effect　of　adverse　pressure　gradient,　and　the　flow　region　along　the　mainstream　direction　of　lower　part　in　tip　clearance,　are　respectively　illustrated.　The　designed　centrifugal　compressor　meets　the　requirement　of　aerodynamic　performance　for　150　kW　class　simple　Brayton　cycle.　©　2020,　Editorial　Office　of　Journal　of　Xi＇an　Jiaotong　University.　All　right　reserved.