Al-Mg-Sc-Zr　alloy　was　formed　by　selective　laser　melting　technology.　The　influence　of　forming　parameters　such　as　laser　power,　scanning　speed,　scanning　distance　and　powder　layer　thickness　on　the　density　of　the　sample　was　studied.　The　formation　mechanism　of　pores　was　analyzed,　and　the　influence　of　laser　energy　density　on　the　density　of　the　sample　was　studied.　The　optimum　processing　parameters　for　SLM　forming　Al-Mg-Sc-Zr　alloy　with　the　highest　density　were　obtained.　The　microstructure　of　the　original　shape　was　observed,　the　phase　composition　was　analyzed,　and　the　differences　of　mechanical　properties　of　the　tensile　specimens　in　different　forming　directions　were　compared.　Finally,　by　studying　the　effects　of　different　aging　processes　on　the　microstructure　and　mechanical　properties　of　the　samples,　the　samples　with　high　density,　almost　no　porosity,　high　strength　and　high　plasticity　were　obtained,　The　yield　strength　is　483.2　MPa　and　the　tensile　strength　is　491.3　MPa,The　elongation　at　break　is　13.2%,　and　the　tensile　property　exceeds　the　forging　standard.