The invention relates to a high-ductility Class F extra thick rack steel plate used at a low temperature and a manufacturing method of the steel plate. The steel plate takes Fe as a basic element and comprises C, Si, Mn, P, S, Cr, Mo, Ni, Cu, Al, V, Nb, N, B and the balance of Fe and impurity elements, wherein the carbon equivalent CEV is 0.75 pounds. The manufacturing method sequentially comprises the procedures of electric furnace smelting, LF (Ladle Furnace) refining, VD (Vacuum Distillation) refining, die casting, ingot heating, cogging rolling, slow cooling control, billet heating, rolling, thermal refining and the like. The thickness of the rack steel plate can reach 180mm, the yield strength is above 690MPa, the tensile strength is between 790-930MPa, the elongation<3> is 20%, the Z-direction performance (percentage reduction of area)<3> of the steel plate is 35%, the Charp impact work below -60 DEG C is greater than 100J, and the comprehensive mechanical property is excellent.