[Problem] To provide a mold-preventing air filter filtration medium and mold-preventing air filter usable against wild bacteria and capable of imparting adequate mold-preventing performance to an air filter having a quick-drying surface. [Solution] A mold-preventing filter filtration medium obtained by immersing a filter material or a reinforcing nonwoven cloth (backing) in a mold-preventing composition in which a water-retaining, high-molecular-weight polymer, a mold-preventing agent, and a binder resin have been dissolved and then drying the material, which is thereby impregnated with the water-retaining high-molecular-weight polymer, mold-preventing agent, and binder resin. The filter material may also be affixed to the reinforcing nonwoven cloth (backing) and used as the mold-preventing filter filtration medium. A mold-preventing air filter comprises the mold-preventing air filter filtration medium processed into a pleated filtration medium that is accommodated in a frame.
