Welding structure fire-resistant and weather-resistant steel with the yield strength being 550 MPa or above comprises components, by weight percent, 0.035 wt%-0.085 wt% of C, 0.25 wt%-0.45 wt% of Si,1.20 wt%-1.55 wt% of Mn, 0.003 wt% or below of P, 0.002 wt% or below of S, 0.05 wt%-0.12 wt% of Mo, 0.25 wt%-0.55 wt% of W, 0.05 wt%-0.12 wt% of Cr, 0.15 wt%-0.37 wt% of Cu, 0.15 wt%-0.35 wt% of Ni, 0.042 wt%-0.068 wt% of Nb, 0.023 wt%-0.044 wt% of Ti, 0.0020 wt%-0.0042 wt% of Ca, 0.0015 wt%-0.0045 wt% of Hf, 0.0020 wt%-0.0047 wt% of N and 0.0025 wt%-0.0045 wt% of O. A production method comprisesthe steps that a casting blank is heated section by section, rough rolling, finish rolling and cooling are sequentially carried out, and air cooling is carried out until the room temperature is reached. According to the welding structure fire-resistant and weather-resistant steel with the yield strength being 550 MPa or above, ReL is 550 MPa or above, Rm is 750 MPa or above, ReL/Rm is 0.78 or below, the ductility A is 30 % or above, the Z-directional performance is 65 % or above, -60 DEG C KV2 is 300 J or above, excellent fire resistance, weather resistance, lamellar tearing resistance, the welding performance, the cold and hot processing performance and the large-deformation resistance are achieved, preheating is not needed before welding, and heat treatment is not needed after welding.