A backlight module and a light emitting diode (LED) light bar thereof are proposed. The backlight module includes a plurality of LEDs, at least one circuit board, a heat sink, a plurality of screws, and a light guide plate (LGP). The plurality of LEDs are arranged on the at least one circuit board. A plurality of screws are arranged on the at least one circuit board and the arrangement method thereof depends on temperature distribution of the at least one circuit board. The plurality of screws are inserted between the plurality of LEDs and are arranged at an unequally distance so that temperature can be evenly distributed over the LED light bar, thereby improving image quality of display devices.