Selective　laser　melting　manufacturing　IN718　powder　with　changed　laser　energy　densities　was　researched.　The　part　to　be　machined　was　divided　into　a　core　and　a　contour,　and　the　selective　laser　melting　manufacturing　was　performed　by　changing　the　laser　energy　density.　Firstly,　a　numerical　model　of　sintering　in　melting　pool　was　set　up,　the　influencing　factors　of　changed　laser　energy　densities　on　the　densification　of　the　part　were　obtained　by　changing　laser　energy　densities,　and　the　microstructure　features　of　the　formed　part　were　observed.　Then,　by　increasing　scanning　for　the　contour　and　changing　the　laser　energy　densities,　the　effect　law　of　changed　laser　energy　densities　on　the　surface　quality　of　the　part　was　also　obtained.　Finally,　the　heat　treatment　processing　was　optimized　and　the　high-temperature　tensile　strength　and　high　temperature　lasting　time　properties　of　the　part　were　improved　to　obtain　the　perfect　surface　quality.　The　results　indicate　when　the　linear　laser　energy　density　is　300　J/m,　the　optimal　densification　level　of　formed　part　is　as　high　as　98.9%.　In　this　condition,　the　typical　microstructures　of　the　formed　part　are　dendrite　and　equiaxial　crystals　along　the　deposition　direction　and　are　equiaxial　crystal　along　the　inside　layer.　Using　the　core　+　contour　scanning　way,　the　optimal　surface　quality　of　the　part　is　obtained　in　laser　energy　densities　of　100　J/m　with　the　roughness　of　3.1　μm.　The　optimal　high　temperature　performance　of　the　formed　part　is　realized　by　solution　+　double　aging　combination　in　1065　,　in　which　the　high　temperature　tensile　strength　is　1356　MPa　and　the　high　temperature　lasting　time　is　34　h.　Results　show　that　the　IN718　nickel-based　super　alloy　manufactured　by　selective　laser　melting　can　satisfy　the　demands　of　complex　aerospace　parts　for　the　densfication　level,　good　forming　quality　and　high-temperature　mechanical　properties.　©,　2015,　Chinese　Academy　of　Sciences.　All　right　reserved.