The　heat　transfer　in　the　channel　with　quasi-streamlined　fin　attached　on　the　wall　has　been　numerically　studied　in　the　periodically　fully　developed　region.　In　range　of　Re　=　100-700,　the　effect　of　the　channel　height　and　the　distance　of　the　fin　to　the　wall　was　investigated.　The　results　reveal　that　the　existence　of　the　quasi-streamlined　fin　disturbs　the　flow　and　changes　the　distribution　of　the　temperature　field.　The　coordination　between　the　fluid　velocity　and　the　temperature　gradient　is　important　to　the　convective　heat　transfer.　Either　increasing　the　distance　of　the　fin　to　the　wall　or　decreasing　the　channel　height　always　deteriorates　the　heat　transfer.　When　evaluated　under　the　constraint　of　the　identical　pump　power　consumption,　the　enhancement　effect　is　also　dependent　upon　the　Reynolds　number.