PURPOSE: To obtain moldings suitable for pulp bleaching, etc., having superior stability and solubility, and scattering no dust by subjecting anhydrous dithionite contg. a stabilizer to dry compression molding in the presence of air having low relative humidity or an inert gas.

CONSTITUTION: To finely powdered anhydrous dithionite is added at least 1 kind of stabilizer selected from the carbonates, phosphates, silicates and carboxylates of alkali metals, urea, hexamethylenetetramine and surfactants. The anhydrous dithionite blended with the stabilizer is charged into the hopper of a compression molding machine, air having ≤50% relative humidity or an inert gas is substituted for the air in the molding machine, and dry compression molding is carried out under 30W200kg/cm2 pressure while keeping the powder at ≤50°C. Thus, the desired moldings of stabilized anhydrous dithionite are obtd.