An anti-reflection optical member has a laminated structure including: a transparent substrate having a first refractive index greater than that of a predetermined medium; a metal-microparticle-containing layer containing metal microparticles; and a dielectric layer having a second refractive index greater than that of the predetermined medium, in this order. At least 60% of the metal microparticles are flat particles with a diameter-to-thickness ratio of 3 or more. Principal planes of the flat metal particles are surface-oriented in the range from 0° to 30° relative to the surface of the metal-microparticle-containing layer. In the metal-microparticle-containing layer, the metal microparticles are disposed without forming a conductive path. The dielectric layer has such a thickness that light reflected at the surface of the dielectric layer of incident light entering the laminated structure from the surface is interfered and canceled by light reflected at the interface between the dielectric layer and the metal-microparticle-containing layer.