In this paper,domestic submerged arc welding technology with large diameter welding wire for steel structures is mainly introduced. According to the output parameters（current,voltage） of the existing equipment in the factory, replacing the existing φ4.8 mm welding wire with a large diameter welding wire for submerged arc welding to improve the deposition efficiency per unit time of submerged arc welding and achieve the purpose of improving the efficiency of submerged arc welding. This article provides a reliable technical basis for efficient welding with large diameter welding wire,and provides a reference for the construction of related projects in the future.