This　study　focus　on　the　heat　transfer　enhancement　and　fluid　flow　characteristics　of　combined　microchannel　with　cone-shaped　micro　pin　fins　(MCPF　for　short)　for　Re　ranging　from　140　to　650.　The　numerical　simulations　are　conducted　to　investigate　the　overall　performance　of　micro　pin　fins　located　in　the　upstream　(case1),　middle　(case2),　downstream　(case3)　and　distributed　throughout　of　the　channel　(case4)　in　a　fixed　number　of　pin　fins.　The　rectangle　smooth　microchannel　(case0)　is　the　reference　channel.　A　three-dimensional　laminar　flow　model　is　performed　and　Navier-Stokes　equations　and　energy　equation　are　solved　by　computational　fluid　dynamics.　The　variations　of　apparent　friction　factor　f　app,ave　and　average　Nusselt　number　Nu　ave　with　inlet　Re　number　are　derived　and　the　thermal　enhancement　factor　(n)　is　applied　to　select　the　best　comprehensive　performance　of　MCPF.　Furthermore,　the　entropy　generation　analysis　is　proposed　to　evaluate　the　heat　transfer　and　flow　friction　irreversibility　loss.　The　results　show　that　the　microchannel　inserted　cone-shaped　micro　pin　fins　improves　the　heat　transfer　accompanied　with　a　higher　pressure　drop　as　compared　with　the　smooth　rectangular　microchannel.　Microchannel　with　uniform　fins　distribution　(case4)　has　the　largest　n　and　the　bottom　wall　temperature　is　the　lowest　and　well-distributed　among　all　cases.　The　entropy　generation　analysis　demonstrates　that　the　heat　transfer　irreversibility　loss　is　larger　than　the　irreversibility　loss　caused　by　flow　friction.　The　total　entropy　generation　of　MCPF　is　lower　than　smooth　rectangular　microchannel.　The　augmentation　entropy　generation　number　of　case4　is　the　smallest　and　case2　is　next　among　all　the　cases.　When　Re<500,　the　N　s　value　of　case3　is　less　than　case1　and　when　Re>500,　the　tendency　is　adverse.　©　2017,　Begell　House　Inc.　All　Rights　Reserved.