PURPOSE: To produce a molded article of gypsum having excellent strength by hydrating hemihydrous or anhydrous gypsum containing a magnetic material, an electrically conductive material, a ferroelectric material, etc., with a theoretical amount of water for hydration reaction.

CONSTITUTION: A water-absorbing polymer including a theoretical amount of water required for hydration reaction in the structure is blended in a powdered state with hemihydrous or anhydrous gypsum containing a magnetic material, an electrically conductive material, a ferroelectric material, etc., and press molded to give a molded article of gypsum having excellent strength. Since water in the water absorbing polymer including water in the structure is used, water can be mixed with gypsum in powder. Further, even at a position having difficulty in supply of water, a molded article of gypsum can readily be produced at an arbitrary position and time by transporting the water absorbing polymer. Hardening of gypsum can be carried out with about 1/3 water required for conventional method and a molded article of gypsum having more excellent strength than that of ordinary cement product can be produced.