A light source module, backlight assembly, and display device including the same are disclosed. In one aspect, the light source module includes a printed circuit board, a plurality of light sources arranged over the printed circuit board, and a plurality of optical lenses respectively arranged over the light sources. Each of the optical lenses has upper and lower surfaces opposing each other. The light source module further includes a plurality of reflection patterns respectively formed on the optical lenses. Each of the reflection patterns includes a first reflection pattern formed on the lower surface of the corresponding optical lens and a second reflection pattern formed on the upper surface of the corresponding optical lens.