PURPOSE: To improve safety and to make a device compact by cascading plural catalyst bodies mutually at intervals, sealing the circumference of a gap between the opposed surfaces of the adjoining catalyst bodies with a cover and providing a voltage to impress a high voltage between the opposed surfaces.

CONSTITUTION: Catalyst bodies 12 and 13 are arranged at a proper interval G, electrodes 14 and 15 are integrally formed by thermal spraying on the opposed surfaces of both, respectively, and the circumference of a gap 19 between the catalyst bodies 12 and 13 is sealed with a cover 20. And air 8 to be processed is introduced into a through hole 7 of the catalyst body 12 by a fan 2, and when it passes the through hole 7, odor components are deodorized in contact with the catalyst. On the other hand, by the high voltage impressed between the electrodes 14 and 15 from a high voltage power source 5, a crona discharge is caused, ozone is generated, and by thew ozone the air 8 to pass the through hole 7 of the catalyst body 12 is sterilized and deodorized. Further, the deodorization is executed by the catalyst in the through hole 7 of the catalyst body 13 to pass next, and simultaneously, the excessive ozone is resolved.