Abstract: Low powered laser-arc hybrid welding of magnesium alloy with cold filler wirewas studied.The effect of welding parameters on weld appearance and penetration was investigated in bead welding experiments of magnesium alloy platewith the thickness of 5 mm and the range of welding parameters was confirmed, such as the electrode height (about 0.75 mm)and the distance between laser and arc (about 1.2 mm).Based on this, magnesium alloy plate with the thickness of 2.5 mm was butt-welded successfully and the welding speed increases to 1 200 mm/min.The weld penetration of hybrid welding with cold filler wire is twice deeper that that of TIG welding and the tensile strength of hybrid welded joint achieves 95% of that of base metal, so magnesium alloy welded joint with high quality can be obtained by hybrid welding with cold wire at a high speed.Besides, the effect of laser pulses on welding process was analyzed.