An optical element includes a substrate that is transparent, and an antireflective film laminated on the substrate. The antireflective film includes, in order from the substrate, a first layer, a second layer, and a third layer. The substrate has a refractive index of 1.80 to 2.05 for the d-line. The first layer is an inorganic oxide film having a refractive index of 1.43 to 1.47 for the d-line and a physical film thickness of 29.0 to 40.0 nm and containing silica as a main component. The second layer is an inorganic oxide film having a refractive index of 2.00 to 2.20 for the d-line and a physical film thickness of 12.0 to 41.0 nm. The third layer is a film having a refractive index of 1.23 to 1.26 for the d-line and a physical film thickness of 110.0 to 130.0 nm and containing silica nanoparticles.
