PURPOSE: To improve considerably the absorptive power of activated carbon by chemisorption simultaneously with the physisorption that the activated carbon possesses by impregnating aluminum dihydrogen triphosphate in the improved structure of the activated carbon.

CONSTITUTION: Aluminum dihydrogen triphosphate which selectively chemisorbs basic gas is impregnated on the rear of a honeycomb-shaped porous body 2 consisting of an inorg. calcined base material 4a and activated carbon powder and granules 4b deposited in the base material. Such deodorizing filter has higher physical adsorptive power as compared to conventional activated carbon or electrostatic types and has the overall adsorptive power for base material higher than any of conventional systems on account of the chemical adsorptive power of the above-described aluminum dihydrogen triphosphate. An excellent deodorizing filter is thus obtd.