A catalyst-supporting porous film includes: a resin layer and catalyst particles dispersed in the resin layer. The catalyst particles are unevenly distributed so as to be present at a surface of the resin layer. Preferably, the catalyst-supporting porous film includes a porous section and a supporting section for supporting the porous section. The number of catalyst particles per unit volume in the porous section is greater than the number of catalyst particles per unit volume in the supporting section. Thus, a catalyst-supporting porous film which has a high catalytic effect can be provided.