To provide a manufacturing method of a light diffusion plate with a primer layer for sufficiently securing an air layer between the light diffusion plate and the other optical film or the like and securing sufficient sticking strength.

The projection and recessed surface 31a of the light diffusion plate 31 for which a convex and concave surface 31a is formed on at least one surface is turned to a lower side and disposed, a primer liquid is applied from the lower side to the convex and concave surface 31a turned to the lower side, and thus the light diffusion plate with the primer layer is manufactured.