Abstract: For the lack of submerged-arc-welding material for corrosion-resistant steel in FCB high line heat energy welding, a variety of new fluxes were developed. Through the comparison of the mechanical properties of the deposited metals by using different fluxes, it is determined that the high alkalinity flux is more suitable for FCB submerged arc welding of corrosion-resistant steel. This flux is mainly composed of CaO, MgO, Al₂O₃, SiO₂ and CaF₂. The welding tests were carried out by using this flux and different heat input. Through the testing and evaluation of tensile, cryogenic impact, bending properties, hardness and corrosion resistance of the welded joints, it is proved that the performance of the corrosion- resistant steel joint with a heat input of 100 kJ/cm is better. All the performance of the joint fabricated by the alkaline flux and the welding process are better than the technical specifications of the welding of corrosion-resistant steel for oil tankers.