A light emitting diode (LED) driving device and an LED driving method thereof are provided. The LED driving device includes a voltage generator, a circuit and a compensation circuit. The voltage generator is used to provide a positive voltage and a negative voltage, and the circuit is coupled to the positive voltage and the negative voltage. Herein, the circuit includes a load and an LED which are coupled to each other in series. The compensation circuit is used to sense voltages of two ends of the load, so as to generate a compensation signal and adjust the positive voltage and the negative voltage through the compensation signal. Therefore, voltage stress of the LED driving device is reduced by using the provided positive voltage and the provided negative voltage.