Abstract: A-MAG welding was proposed to obtain the welded joints with high quality.The experiment results show that A-MAG weld appearance,internal quality of welded joint and the welding operation performance are very well.Experiments also show that the A-MAG welding can improve weld penetration, which is compared with MAG welding under the same heat input.The tensile strength and bending strength of A-MAG welded joint are not reduced,while impact strength is improved,especially in the HAZ.Dimples size in fracture appearance of A-MAG welded joint is finer.It is showed that the active MAG welding can improve the welding quality and weld penetration of weathering resistant steel,which is applicable in engineering application.