Abstract: Aiming at the phenomenon that the gas hole ratio of 2mm stainless steel electrical distribution box is as high as 4%by hand-held laser welding,the reasons of porosity are analyzed.Through a series of welding process tests,The welding process of pulsed laser welding,controlling assembly gap less than 0.1mm,optimizing laser power to about 1400W,reducing gas flow to 18L/min,increasing swing width by 3mm and swing width by 30Hz can effectively inhibit the porosity of butt weld and outer corner vertical weld of electrical distribution box.