To provide a method for deodorizing a malodorous gas, which enhances a deodorizing capacity and reduces an equipment cost, and an apparatus therefor.

Microorganisms are bonded to a packed bed wherein a planar chemical fiber packing material having a water absorbing functions, which is obtained by impregnating chemical fibers with a water absorbing polymer, is arranged and the malodorous gas is brought into contact with this packed bed to be deodorized biologically. The planar chemical fiber packing material to be used is fixed to the side surface of a support made of plastics and microorganisms are bonded to the packed bed, wherein the packing material obtained by fixing the water absorbing polymer to the support in a thin layer state is arranged, and the malodorous gas is brought into contact with this packed bed to be deodorized biologically.