Abstract: The present application discloses a backlight module and a display device thereof. The backlight module includes a light guide plate, a side part thereof including a light incident surface; a light bar, including a circuit board and a plurality of photoelectric elements disposed on the circuit board, wherein the circuit board includes spacing parts located between two adjacent photoelectric elements, and light emitting surfaces of the photoelectric elements correspond to the light incident surface; and a reflective sheet, disposed between the light guide plate and the light bar, wherein the reflective sheet includes hollowed parts, and the hollowed parts are correspondingly disposed between the light emitting surfaces and the light incident surface, so as to reduce a reflective brightness of the photoelectric elements.