In　this　study,　the　porous　tungsten　matrices　of　dispenser　cathodes　were　prepared　by　a　new　method　of　three-dimensional　selective　laser　melting,　and　the　relationship　between　3D　printing　process　and　porosity　of　matrix　was　studied.　The　emission　performance　of　the　cathodes　impregnated　with　barium　aluminates　with　and　without　addition　of　Scandia,　have　been　measured.　It　was　found　that　the　emission　property　of　the　cathodes　with　machined　and　W-coated　surface　is　similar　to　that　of　traditional　B-type　cathodes,　and　the　addition　of　Sc2O3　in　the　impregnations　improved　the　emission　capability　of　cathode　significantly.