The invention provides a water resistant molding material that can be stably manufactured while being excellent in water resistance after dried, and a producing method for the water resistant molding material. The water resistant molding material comprises a binder resin containing a polyvinyl alcohol resin, a viscosity control agent, water and a filler, wherein the concentration of acetate ions is adjusted in the range from 500 to 12,000 ppm by blending, for example, an acetate ion controlling agent (such as NH.sub.4NO.sub.3, NaOH and KCl).