A method for producing a blast furnace mantle used armor plate belongs to the medium plate production technology field. The production process includes the following steps: molten steel is smelted bya converter and treated by LF and RH furnaces, thereby obtaining the accredited 250mm continuous casting via casting; then the continuous casting is heated to 1150-1300 DEG C in the furnace for 200-300min, and subjected to high-pressure water scale removal after being out of the furnace and rolling after entering a 4300mm rolling mill; the rolled armor plate is subjected to water-cooling with thefinal cooling temperature of 670-720 DEG C; the water-cooled armor plate is subjected to normalizing treatment at the normalizing temperature of 890-930 DEG C after off-line-stacking for 36-48h, and the cooling manner is air-cooling. The method has the advantages of higher armor plate yield, reduced production cost and simple process flow.