A dielectric multilayer film is composed of a plurality of layers on a substrate. The plurality of layers includes at least one low refractive index layer and at least one high refractive index layer. The uppermost layer farthest from the substrate is the low refractive index layer. The high refractive index layer disposed on a substrate side of the uppermost layer is a functional layer containing a metal oxide with a photocatalytic function. The uppermost layer is a hydrophilic layer containing a metal oxide with a hydrophilic function and has pores that partially expose a surface of the functional layer. The average width of the pores is equal to or greater than 5 nm.