Silicon-based　fractal　tree-shaped　microchannel　heat　sinks　with　different　bifurcation　angles　were　designed　and　manufactured.　The　heat　transfer　and　pressure　drop　characteristics　of　the　fractal　microchannel　network　were　experimentally　studied　under　an　inlet　Reynolds　number　of　Re0　=　500–1700.　The　results　showed　that　compared　with　the　traditional　linear　microchannel　heat　sink,　the　fractal　microchannel　heat　sinks　could　achieve　considerable　flow　drag　reduction　and　heat　transfer　enhancement.　Maintaining　the　chip　temperature　below　85　°C,　the　pressure　drop　can　be　reduced　by　up　to　92%,　and　the　heat　transfer　coefficient　can　be　enhanced　by　1.5　times　of　the　fractal　microchannel　network　at　the　same　flow　rate.　The　optimized　bifurcation　angle　of　the　fractal　network　was　recommended　to　be　30°.　The　COP　of　fractal　microchannel　heat　sinks　with　a　bifurcation　angle　of　30°　can　reach　12–13　times　that　of　the　linear　microchannel.　©　2022　Elsevier　Masson　SAS