There is provided a catalyst module having a waste liquid inlet passage for the inflow of a waste liquid, whose partition wall is formed of fibrous activated carbon, in which: the fibrous activated carbon is impregnated with or contains a catalyst; and a waste liquid in the waste liquid inlet passage passes through the partition wall and is discharged out of the waste liquid inlet passage. Further, there is provided a catalyst module, in which a plurality of waste liquid inlet passages is arranged in the form of a bundle. In the catalyst module are also provided partition walls formed of a fibrous activated carbon layer prepared by laminating a plurality of the fibrous activated carbon in the form of sheets.