To provide an inorganic cement plate production process which involves preparing a material that consists essentially of cement and powdery silica stone and also contains reinforcing fiber and fumed silica, and producing an inorganic cement plate from the prepared material by a sheet-making method, and enables, by using the fumed silica, production of the objective inorganic cement plate product having high strength and high durability without causing any reduction in productivity.

This production process involves preparing an aqueous slurry by mixing a powdery main material consisting essentially of cement with reinforcing fiber, and producing an inorganic cement plate from the prepared aqueous slurry by a sheet-making method, wherein fumed silica and a polyether- based, comb-like-branched high polymer dispersant are concurrently added to the above aqueous slurry to mix them together and the resulting aqueous slurry is subjected to papermaking.