In　this　work,　the　weldability　of　the　alloy　Al-Mg-Mn-Zr-Er　with　high　power　Nd:YAG　laser　has　been　studied.　Samples　were　subjected　to　three　different　welding　heat　inputs　to　obtain　various　weld　beads.　The　main　objective　of　the　present　work　has　been　to　investigate　the　change　of　microstructure　and　microhardness　at　the　Al-Mg-Mn-Zr-Er　laser　weld　beads.　Results　showed　that　the　top　width　of　the　bead　was　larger　at　the　higher　laser　power.　Grain　structure　refinement　was　found　in　welded　metal,　especially　at　higher　laser　power.　It　was　also　verified　that　the　microhardness　of　weld　bead　was　raised　with　the　decrease　of　laser　power,　due　to　the　microstructure　refinement　at　the　condition　of　lower　laser　power.