In　this　work,　Al-0.88Er-0.78Zr　(wt%)　alloy　was　fabricated　via　laser　powder　bed　fusion　(LPBF).　The　microstructure,　precipitates　distribution,　electrical　conductivity　and　hardness　of　as-built　and　aging　treatment　specimens　were　carefully　characterized.　Results　show　that　LPBF　process　greatly　expand　the　solid　solubility　of　Er　and　Zr　in　Al.　The　addition　of　Er　can　significantly　refine　the　grain　size　and　form　a　bimodal　grain　structure　consisting　of　fine　equiaxed　grains　(grain　size　~0.53　&　PLUSMN;　0.15　mu　m)　at　the　boundary　of　molten　pool　together　with　coarse　columnar　grains　(width　2.57　+/-&　nbsp;0.84　mu　m)　at　the　center　of　molten　pool.　After　375　celcius　for　3　h　aging　treatment,　the　particles　on　the　grain　boundary　inhibit　the　grain　growth;　at　the　same　time,　a　large　number　of　Al3(Er,Zr)　particles　with　L12　structure　and　size　of　2.25　+/-&　nbsp;0.3　nm　are　precipitated,　which　plays　a　major　role　in　enhancing　the　hardness　with　the　peak　hardness　of　about　89.24　&　PLUSMN;　3.77　HV.　Er　and　Zr　elements　are　proved　to　be　an　alternative　way　of　the　additive　elements　for　developing　a　new　3D　printing　high-strength　aluminum　alloy.(C)&　nbsp;　2022　Elsevier　B.V.　All　rights　reserved.