The invention provides a backlight module, an LCD device and a light source of the backlight module. The backlight module includes an LED chip, and a heat sink; the LED chip and a circuit thereof are directly arranged on the heat sink. In the invention, because the LED chip of the backlight module and the circuit thereof are directly arranged on the heat sink, heat emitted by the LED chip can be conducted out through the heat sink with good heat dissipation effect; thus, the inside temperature of the backlight module is reduced, and the heat dissipation efficiency of the backlight module is increased.