A backlight assembly that allows a more efficient light usage and thinner device size is presented. The backlight assembly includes a first light guide and a second light guide that each has a light incident face, a light exiting face, and a light reflective face. The light reflective face of the first light guide has a first light reflective face portion and a second light reflective face portion while the light reflective face of the second light guide has a third light reflective face portion and a fourth light reflective face portion. The light reflective member has a first reflection face arranged at the second light reflection face portion and a second reflection face arranged at the fourth light reflective face portion, and the light source supplies light to the first and second light incident faces. The light incident faces are on the same side of the light guiding members.