Abstract: To reduce big plate of 5A06 aluminum alloy laser welding defects, which enhances the stability of welding process, using a laser beam in a certain way of scanning new welding method, welding laser beam was studied different trajectories, amplitude, frequency of deep penetration laser welding aluminum alloy weld porosity, and the welding groove design optimization based on the application of narrow gap scanning laser wire filling welding technology for 130 mm thick 5A06 aluminum alloy welding test. The results show that when the scanning amplitude of the laser beam is greater than 1 mm and the scanning frequency is near the highest frequency, the porosity of the weld can be greatly reduced. The welding method of narrow gap laser scanning wire filling was adopted to obtain the high-quality welding joints of 130 mm 5A06 aluminum alloy with average porosity of 1%, no side wall non-fusion, interlayer non-fusion, crack and other welding defects.