To easily manufacture a mineral plate having a film including no defect such as foam, foam breakage or the like on a surface without using a special facility.

The method for manufacturing a mineral plate 6 comprises the step of forming a skin layer 4 having a thickness of a protruding size or more of a fluffed reinforcing fiber 2 on a surface of a base plate 3 for the mineral plate and made of a hydraulic material 1, on the surface of the plate 3 for the plate 6 during a period from a papermaking step to a curing step in the case of manufacturing the plate 6 by papermaking, molding, curing and coating a hydraulic raw material slurry containing the material 1 and the fiber 2 as main components, thereby eliminating the fluffing.