A multi-functional cabin air filter includes a dust collecting filter layer for collecting fine dust; an oxidation catalyst filter layer for oxidizing nitrogen monoxide into nitrogen dioxide; and an adsorption filter layer for adsorbing nitrogen dioxide and volatile organic compounds, wherein antimicrobial nanoparticles are applied to at least one of the dust collecting filter layer, the oxidation catalyst filter layer and the adsorption filter layer. This cabin air filter has dust collecting, denitrifying, deodorizing and antimicrobial functions, and it may be utilized in various ways for air purification in a limited space such as a vehicle.