The invention discloses a welding method for improving the stability of a laser-electric arc composite welding process, and relates to the field of material processing engineering. Low-temperature treatment is carried out on shielding gas, independent paraxial shielding gas is added on one side of an electric arc welding gun, and the axis direction of the paraxial shielding gas points to a laser action spot and the space above the laser action spot, namely where photoinduced plasma is generated during welding, and the effect of improving the stability of the composite welding process is realized. The welding method is high in welding efficiency, air holes and hot cracks are inhibited, the mechanical property is improved, and the welding stability of a long welding joint is improved.