The　AlSi10Mg　alloy　fabricated　using　selective　laser　melting　(SLM)　has　attracted　attention　because　of　its　excellent　quality　and　properties.　However,　the　mechanical　properties　of　SLM　AlSi10Mg　alloy　cannot　meet　the　requirements　of　the　high　strength　of　aluminum　alloys　in　the　aerospace　industry.　To　improve　the　mechanical　properties　of　SLM　AlSi10Mg　alloy,　AlSi10Mg-Er-Zr　powders　were　prepared　using　in　situ　alloying　mechanism　and　gas　atomization.　The　relative　density,　microstructure,　and　mechanical　properties　of　SLM　AlSi10Mg-Er-Zr　alloys　have　been　investigated.　The　results　show　that　the　relative　density　of　AlSi10Mg-Er-Zr　alloys　fabricated　using　SLM　reaches　99.20%.　The　SLM　AlSi10Mg-Er-Zr　alloy　has　a　microhardness　value　of　156.5　HV.　The　ultimate　tensile　strength　(UTS)　and　yield　strength　(YS)　of　the　SLM　AlSi10Mg-Er-Zr　alloy　can　reach　461　and　304　MPa,　respectively.　Compared　with　the　conventional　AlSi10Mg　alloy,　the　microhardness　has　been　increased　by　25.8%;　the　UTS　and　YS　are　increased　by　22.6%　and　26.7%,　respectively.　The　fine-grain　and　solid　solution　strengthening　associated　with　SLM　processing　with　the　addition　of　Er　and　Zr　elements,　as　a　result　of　increased　grain　size　refinement　and　solid　solubility　of　Si　element　in　the　alpha-Al　matrix,　are　responsible　for　the　improvement　in　the　mechanical　properties.