Abstract: A process for deodorizing an exhaust gas containing at least one smelly material selected from the group consisting of acidic smelly materials, such as hydrogen sulfide, mecaptans, dimethyl sulfide, dimethyl disulfide and the like; basic smelly materials, such as ammonia, amines and the like; and smelly organic material, such as ketones, alcohols, aldehydes, carboxylic acids and the like is disclosed. Vapor-liquid contact of the exhaust gas with a sodium hypochlorite solution is caused in the presence of a catalyst which is a mixture of nickel peroxide and at least one carrier. In the presence of the catalyst, placed in a column, sodium hypochlorite solution falling from the upper portion of the column contacts exhaust gas rising from the lower portion of the column to promote catalyst oxidation reaction.