The welding distortion of aluminum alloy end walls was taken as the example. The reasons of welding distortion of Al alloy end walls with plate-girder structure were analyzed and a suit of process program for producing end walls was summarized with preferable assembly sequence,high assembly quality,suitable welding procedure and prefabricated distortion to reduce welding distortion. By these means,the difficulty of repair and workload were reduced,the efficiency of production was increased,and high standard quality products were made.