The invention discloses a welding material composition for soft liner single-face submerged arc automatic welding. A welding stick in the composition comprises components including, by mass percent, 0.08%-0.17% of C, 0.01%-0.04% of Si, 1.0%-2.5% of Mn, 0.1%-0.5% of Cr+Ni, 0.010%-0.025% of S, 0.010%-0.025% of P and the balance Fe powder. A surface welding agent comprises components including, by mass percent, 10%-20% of SiO2, 15%-35% of MgO, 5%-15% of TiO2, 7%-20% of Al2O3, 5%-20% of CaO, 0.01%-0.04% of S, 0.01%-0.04% of P, 0.01%-0.1% of H2O, 0.1%-0.2% of impurities and the balance Fe powder. Filling powder comprises components including, by mass percent, 0.004%-0.01% of C, 0.01%-0.4% of Si, 1.0%-2.5% of Mn, 2.0%-5.0% of Ni, 0.2%-1.0% of Mo, 0.02%-0.04% of S, 0.02%-0.04% of P and the balance Fe powder. By means of the welding material composition, the production efficiency is improved by 3-5 times, and cost is reduced by 50%-60% compared with the cost of imported similar welding materials.