To provide a building board on which a decorative sheet made of a hardened body and having projecting parts with flat tops is deposited, the coupling component of the hardened body being calcium carbonate, with the surface of the decorative layer protected when it is handled for transportation, installation, etc., for effectively preventing the same from being fouled.

A building board has a decorative layer on the surface thereof, the decorative layer being made of a hardened body whose coupling component is calcium carbonate. In that case, a plurality of projecting parts the tops of which are flat surfaces 2 present on a common plane and the planar shapes of which are generally indefinite are formed on the surface of the decorative layer, and a continuous protective sheet 4 having a peel strength of 200 mN or more is deposited over the flat surfaces of the projecting parts without the intervention of a separate adhesive layer.