By　using　the　hybrid　welding　technology　of　fiber-laser　and　VPTIG　(variable-polarity　tungsten　inert　gas　arc　welding),　the　A7204　aluminum　alloys　are　welded　with　different　filler　wires.　The　microstructures　and　mechanical　properties　of　these　joints　by　this　hybrid　welding　are　analyzed,　and　the　softening　behavior　and　mechanism　of　these　joints　are　also　investigated.　The　results　show　that　the　upper　part　of　the　weld　with　ER5087　filler　wires　presents　the　finest　microstructure　with　narrow　dendrite　arms.　After　the　natural　aging　of　90　days,　the　mechanical　properties　of　joints　welded　with　three　kinds　of　filler　wires　are　similar,　and　the　tensile　specimens　fracture　basically　in　the　heat-affected　zone　which　is　close　to　the　base　metal.　The　microhardness　of　these　joints　welded　with　three　kinds　of　filler　wires　in　the　heat-affected　zone,　1.6-2　mm　away　from　the　fusion　line,　is　the　highest,　in　contrast,　the　softening　zone　obviously　occurs　in　the　heat-affected　zone,　3-7　mm　away　from　the　weld　center.　In　the　heat-affected　zone,　there　exist　the　obvious　aging　hardening　zone　and　recrystallization　softening　zone,　and　the　natural　aging　has　an　obvious　effect　on　the　softening　of　heat-affected　zone.　©　2018,　Chinese　Lasers　Press.　All　right　reserved.