To provide a method for producing an aldehyde gas deodorant which has high aldehyde deodorizing performance, and which is negative for mutagenicity and excellent in safety, and a deodorant processed product. A method for producing an aldehyde gas deodorant, the method comprises the steps of: preparing a deodorizing composition containing a dihydrazide compound, a water-containing inorganic powder, and water； and heating the deodorizing composition at a temperature of from 45° C. to 90° C. so that water remains in an amount of 4.5% by mass or more, based on the total mass of the deodorant produced, and wherein the aldehyde gas deodorant is negative for mutagenicity measured by an AMES test.
