A backlight assembly and display device having the same. The backlight assembly may include a light source, a light guide formed at one side of the light source, at least one optical sheet disposed on the light guide and have first to fourth sides and first to fourth corners and a mold frame which accommodates and fixes the optical sheet, wherein the optical sheet includes a first tab which protrudes in a same plane as the optical sheet and in a direction perpendicular to the second side while being adjacent to the second corner, and a second tab which protrudes in the same plane as the optical sheet and in a direction perpendicular to the third side and is disposed to be between and spaced apart from the third corner and the fourth corner.