The antireflection film is provided on a surface of a light-transmitting substrate and includes a thin multi-layer film and a fine unevenness layer that are laminated in this order from the substrate side. The thin multi-layer film includes multiple layers. The fine unevenness layer has a structure in which an uneven structure having a shorter average pitch than a wavelength of used light is provided and in which a refractive index to the used light changes continuously depending on a continuous change in a space occupation of the uneven structure in a thickness direction of the thin multi-layer film. The multiple layers include: an oxide film having a relatively high refractive index that is formed of at least two metal elements or is formed of silicon and at least one metal element; and an oxynitride film having a relatively low refractive index.