To improve mechanical strength of a gypsum molding without impairing fluidity and pourability and surface smoothness of the obtained molding by adding chemical foaming agent for mainly generating nitrogen gas at ambient temperature and inorganic needle compound in the case of obtaining gypsum molding.

Slurry containing calcined gypsum, inorganic needle compound and chemical forming agent for mainly generating nitrogen gas at the ambient temperature is charged in a form, and cured. At least one type selected from natural inorganic needle compound and synthesized inorganic needle compound is added. Thus, high mechanical strength is provided, and wear characteristics are lartly improved. And, gypsum molding is foamed in about 1.0 to 2.0 times to be light. Its surface smoothness is remarkably high. Further, dehydrating velocity is fast, pourability is satisfactory and practical.