Micro-jet　impingement　cooling　heat　sink　is　used　to　enhance　heat　transfer　owing　to　the　very　thin　hydrodynamic　and　thermal　boundary　layers　in　the　impingement　region　when　a　jet　impinges　on　a　surface.　A　copper　micro-jet　impingement　cooling　heat　sink　consisting　of　five　copper　sheets　is　designed　in　this　paper　and　the　jet　diameter　is　0.150　mm.　Experiments　are　conducted　to　investigate　the　character　of　heat　transfer　in　the　heat　sink　with　de-ionized　water.　The　experiment　results　indicated　that　adopt　micro-jet　arraying　cooling　is　not　only　strengthen　heat　transfer　by　increasing　the　number　of　stay　point,　but　also　decrease　heat-exchange　surface　difference　in　temperature　efficiently.　The　heat　resistance　of　heat　sink　will　decline　with　the　increase　of　pump　power,　then　with　the　continuous　increasing　of　pump　power　the　heat　resistance　change　slowly.