Abstract: In view of the deformation problem of aluminum alloy box body during welding forming process, this paper analyzes the causes and puts forward some solving measures, the welding process was optimized by using special welding fixture, adjusting welding sequence and optimizing welding parameters, which effectively reduced the deformation of the box during welding, the product can meet the requirement of deformation. By solving the problem of the deformation of the box, the welding experience of the super-long thin-wall aluminum alloy box parts is accumulated, which can be used for reference in the welding process of similar parts in the future.