Thermal　management　has　become　crucial　to　ensure　the　performance　and　reliability　of　high　power　chips　and　micro-cooling　systems.　The　forced　convective　heat　transfer　of　microchannel　heat　sink　is　a　very　promising　method.　In　this　paper,　experiment　is　used　to　perform　temperature　and　pressure　drops　and　numerical　simulation　is　used　to　understand　and　interpret　the　complex　thermal　behavior　by　presenting　the　flow　field　in　the　current　complex　corrugation　microchannel　heat　sink.　The　comprehensive　performance　is　evaluated　by　total　thermal　resistance　and　thermal　enhancement　factor.　Compared　with　the　equivalent　rectangle　microchannel　heat　sink,　the　average　temperature　and　maximum　temperature　is　reduced　obviously　and　temperature　distribution　is　more　uniform　albeit　with　higher　pressure　penalty　for　flow　rates　larger　than　100　ml/min.　It　is　observed　that　the　vortex　becomes　bigger　and　moves　to　the　middle　of　channel　with　increasing　of　flow　rate.　The　enhance　heat　transfer　mechanisms　can　be　contributed　to　the　heat　transfer　area　enlarged,　thermal　boundary　interrupted　and　redeveloped,　chaotic　advection,　hot　and　cooling　fluid　better　mixed　by　vortex　formed　in　the　reentrant　cavity.　The　pumping　power　is　reduced　18.99%　when　total　thermal　resistance　equals　to　0.446　K/W,　compared　with　rectangle　microchannel　heat　sink.　The　thermal　enhancement　factor　can　reach　1.24　for　Reynolds　number　of　611.　Therefore,　complex　corrugation　microchannel　heat　sink　is　more　economical　for　chip　cooling　system.　(C)　2015　Elsevier　Ltd.　All　rights　reserved.