The　fluid　field　pressure　distribution　was　obtained　using　the　fluid-solid　interaction　technology　with　the　combination　of　computational　fluid　dynamics　(CFD)　flow　analysis　and　finite　element　method　(FEM)　structure　analysis.　The　aerodynamic　loads　were　exerted　on　the　solid　blade　surfaces　to　analyze　strain　and　stress.　Then　the　centrifugal　force　was　added　as　another　load　to　the　blade　and　the　deformation　of　the　centrifugal　blade　under　working　condition　was　achieved.　The　running　blade　profile　was　gained　by　calculating　the　deformation　magnitude　of　the　solid　grid　nodes,　and　the　fluid　field　in　the　deformed　blade　passage　was　analyzed.　To　evaluate　the　influence　of　deformation　on　the　impeller　performance　with　tip　clearance　variation,　the　calculations　of　three　kinds　of　tip　clearance　distributions　were　conducted.　The　results　show　that　the　deformation　under　the　aerodynamic　load　is　only　about　1%-3%　of　that　under　the　total　load　and　the　largest　deformation　occurs　at　the　blade　inducer　tip.　The　tip　clearance　decreases　from　the　inlet　to　the　outlet　of　the　blade　because　the　deformed　blade　root　and　tip　are　close　to　the　casing.　When　the　tip　clearance　of　the　undeformed　blade　is　0.5　mm,　the　tip　clearance　at　the　deformed　blade　outlet　can　decrease　by　up　to　50%.　In　addition,　the　isoentropic　efficiency　of　the　centrifugal　impeller　at　low　flow　rate　decreases　by　0.9%-1.8%　because　of　the　variations　of　the　tip　clearance　and　the　blade　profile.