To provide a newly low-temperature plasma deodorizing method and deodorizing apparatus having a high deodorizing efficiency and a catalyst with long lifetime, and capable of reducing decomposed material attached on the surface of the catalyst.

In a deodorizing method in which gas to be treated is contacted with an oxidation promoting catalyst after being subjected to a low-temperature plasma treatment, the oxidation promoting catalyst is kept in a wet state. In the deodorizing apparatus 10 including a high-voltage discharging section 1 capable of generating low-temperature plasma and a catalyst section 2 filled with the oxidation promoting catalyst 6, a water supplying means 7 capable of keeping the oxidation promoting catalyst in a wet state is also included.