A backlight assembly includes a light source generating light and a first optical member diffusing the light. The first optical member includes a first diffusion member provided on an exit surface of the first optical member, from which the light exits, to diffuse the light. The first diffusion member includes a plurality of edges each having a curved shape and extending between the exit surface and a vertex of the first diffusion member. Accordingly, the light exiting through the exit surface is effectively diffused by the edges of the first diffusion member.