The invention discloses a high-ductility electrogas welding self-shielded flux-cored wire, which comprises a steel strip and a welding flux wrapped in the steel strip. The weight factor of the welding flux in the overall weight of the wire is 0.2-0.3, and by weight percent, the steel strip comprises 0.01-0.055% of C (carbon), 0.01-0.03% of Si (silicon), 0.10-0.30% of Mn (manganese), 0.005-0.060% of Al (aluminum), 0.007-0.015% of P (phosphorus), 0.007-0.015% of S (sulfur) and the balance Fe (ferrum). By the overall weight of the wire, the wire comprises 2.0-6.0% of fluoride, 1.0-4.0% of oxide, 0.2-1.0% of carbonate, 1.0-4.0% of Mn, 0.2-1.2% of Si, 0.4-2.0% of Ni (nickel), 0.1-1.0% of Mo (molybdenum), 0.05-0.2% of Cr (chromium), 0.05-0.2% of V (vanadium) and the balance Fe. When the wire is used for welding, weld strength is higher than 500MPa, impacting energy at the temperature of -30 DEG C is higher than 50J, and the wire is mainly applicable to occasions of heavy and rapid welding for thick plates.