The　interrupted　microchannel　heat　sink　with　spoilers　in　transverse　zones　is　a　novel　structure.　It　consists　of　a　set　of　separated　zones　adjoining　parallel　microchannels　and　transverse　microchambers　with　spoilers.　The　heat　transfer　enhancement　depends　strongly　on　the　disturbed　effect　by　the　spoilers　in　transverse　zones.　The　structural　parameters,　including　the　lengths　and　widths　of　the　rectangular　microchannel　regions　and　the　spoilers　have　an　important　influence　on　the　behavior　of　fluid　flow　and　heat　transfer　in　the　microchannel　with　spoilers　in　transverse　zones.　This　paper　reports　an　investigation　of　the　influence　of　structural　parameters　with　three-dimensional　numerical　simulation　over　the　whole　heat　sink.　The　steady,　laminar　flow　and　heat　transfer　equations　were　solved　by　the　finite-volume　method.　The　analysis　shows　that　when　the　lengths　of　inlet　and　outlet　zones　both　are　5　mm　and　the　heat　transfer　length　is　10　mm,　the　optimized　structural　parameters　are　L1/L2=4.1875,　L2=0.4　mm,　W1=W2=0.35　mm,　and　0.52/H1