PURPOSE: To efficiently capture malodorous substances alone from a gas for deodorization by using a metal ion exchange zeolite as a deodorant.

CONSTITUTION: A naturally occurring or synthetically produced zeolite having pores of about 3 - 9 for adsorbing malodorous substances is brought into contact with the aqueous nitrate or chloride solution of at least one kind of metal ions selected from Mn, Fe, Co, etc. A metal ion exchange zeolite thus obtained is used as a deodorant and the metal ions therein have a unique action on the malodorous substances and capture efficiently such substances alone from a gas for deodorization. The malodorous substances, once captured, are fixed in the afore-said zeolite, unable to be easily removed.