Abstract: Laser welding provides an effective technical method for power battery aluminum alloy sheet welding, but the traditional laser welding process is easy to produce spatter, porosity and other defects under the requirement of high welding speed, which will affect the service performance of component. In this paper, the regulation and control of laser lap welding of aluminum alloy sheet with adjustable ring spot are studied, and the influence law of center-ring laser power on weld forming was expounded. On this basis, the high-speed stable welding process window with no spatter, little porosity and large lap surface width was identified. In the range of the process window, the multi-objective optimization of process parameters was further carried out by taking small penetration fluctuation and large bonding width as targets. It has been proved that the welding speed is above 70 mm/s, the welding width of the lap surface is increased by 8.89%, the fluctuation of the welding depth is less than 10%, there is no obvious forming defect, and the forming quality of the weld is further improved.