Method of producing weathering steel by thin slab casting and rolling process based on ESP

The invention provides a method of producing weathering steel by the thin slab casting and rolling process based on ESP. The method comprises the following steps of selecting raw materials in percentage by mass: 0.01-0.06 percent of C, 0.30-0.60 percent of Si, 0.30-0.60 percent of Mn, 0.05-0.12 percent of P, 0.25-0.45 percent of Cu, 0.30-0.80 percent of Cr, smaller than or equal to 0.30 percent of Ni, smaller than or equal to 0.01 percent of S and the balance of an iron element; sequentially smelting the raw materials by a converter and an LF furnace; treating molten steel formed by LF furnace smelting by an ESP production line to produce hot rolled strip steel with different thicknesses, wherein in the ESP production line, the molten steel formed by LF furnace smelting is enabled to enter a continuous casting machine, and is cast at the pulling rate being larger than or equal to 4.5m/min, and the temperature of a finish rolling outlet is larger than or equal to 820 DEG C; and cooling the hot rolled strip ste