Abstract: By using KOBELCO robot off-line programming method and remote control single wire welding system, Q690E low-alloy high strength steels were welded by MAG welding with MG-S88A welding wire. Based on the analysis of Q690E weldability, by properly designing welding procedure and strictly controlling welding factors. The problem of the low impact property of the joint was solved. The results show that KOBELCO robotic MAG welding method is suitable for Q690E steel. According to marine standards, the mechanical properties of welded joints were tested. The tensile and bending properties of the welded joint meet the requirement of testing standards. The impact toughness at the welding center, fusion area, fusion zone + 2 mm, fusion zone + 5 mm can be assured to be higher than 69 J at -40 ℃.