A coating method of a board for producing a concrete product and a board coated by the same are proposed. The coating method is advantageous in that the whole surface of a board can be rapidly coated and dried to prevent surface corrosion of the board and to prevent further corrosion on a damaged surface of the board, thus improving the durability of the board and the quality of the produced concrete products. The coating method includes: removing residues existing on an outer surface of the board by blowing high-pressure air to an upper surface and a lower surface of the board for producing a concrete product; coating by spraying coating liquid to the outer surface of the board from which the residues have been removed; and drying the coating liquid by blowing high-pressure air to the outer surface of the board.