Abstract: The invention discloses a filtering device (1) for neutralizing volatile bad smells present in the atmosphere or carried by a flow of gas (5). The device comprises at least a layer (3) of natural zeolite material of set thickness impregnated with an aqueous solution with, for 100 parts by weight of zeolite, about 5 to about 20 parts by weight of the aqueous solution. This aqueous solution comprises for 1000 parts by weight of water, between about 1 part and about 20 parts by weight of a composite mixture comprising, for one part of ammonium ions or equivalent, one part of at least of one perfuming and/or deodorising composition.