To　reduce　aerodynamic　loss　and　noise　caused　by　the　tip　leakage　flow　in　an　axial　flow　fan,　fused　winglets　are　added　on　the　top　of　the　blades　of　the　axial　flow　fan.　The　influence　of　winglets　on　the　flow　field　and　sound　field　of　the　axial　flow　fan　are　investigated　with　numerical　method　of　large　eddy　simulation　and　FW-H　acoustic　analogy.　The　tip　leakage　flows　are　compared　under　the　influences　of　winglets　with　different　camber　angles.　Analyzing　the　flow　field　and　sound　field,　and　comparing　the　vorticity　distributions　around　the　fused　blade　tip　winglets　with　different　camber　angles　and　the　surface　sound　pressure　pulsation,　the　effect　of　the　different　camber　angle　of　winglets　on　the　tip　leakage　flow　and　the　influence　of　the　tip　winglets　on　the　fan　aerodynamic　performance　and　noise　characteristics　are　discussed.　The　results　show　that　the　winglet　can　effectively　control　the　development　of　tip　leakage　vortex　and　tip　separation　vortex,　reduce　the　aerodynamic　noise　of　the　axial　flow　fan,　and　improve　the　static　pressure　efficiency　of　the　axial　flow　fan.　The　static　pressure　efficiency　increases　by　1.1%　and　noise　decreases　by　5.0　dB　by　utilizing　the　blade　tip　winglets　with　20°　camber　angle.　The　aerodynamic　noise　caused　by　tip　leakage　flow　is　mainly　broadband　noise,　and　the　winglet　can　significantly　weaken　the　broadband　noise.　Optimizing　the　camber　angle　of　the　winglet,　the　noise　reduction　can　be　achieved　without　damaging　the　aerodynamic　performance.　©　2020,　Editorial　Office　of　Journal　of　Xi＇an　Jiaotong　University.　All　right　reserved.