The present invention provides a light diffusion member, a method for producing the same, and a display device. The light diffusion member is provided with: a light-transmissive substrate; a plurality of light diffusion sections; a light-blocking layer; and a joining layer. The plurality of light diffusion sections are disposed at a first region at one surface of the substrate. The light-blocking layer is disposed at a second region that differs from the first region at the one surface of the substrate. The joining layer is disposed overlapping across the plurality of light diffusion sections. Each light diffusion section is formed in a manner so that the side at the one surface of the substrate forms a light exit end surface, the surface opposite the light exit end surface forms a light entrance end surface, and the cross sectional area increases from the light exit end surface to the light entrance end surface. In at least one of the light diffusion sections and the joining layer, a plurality of light scattering bodies formed from a material having a different photorefractive index from that of the constituent material of the light diffusion sections or the constituent material of the joining layer are disposed in a diffused manner.