The present invention relates to a high efficiency LED driver and driving method thereof. In one embodiment, a high efficiency LED driving method configured for a LED device can include: (i) receiving a DC bus voltage and generating a driving voltage for the LED device through a power switch; (ii) comparing the DC bus voltage against a sum of the driving voltage and a first reference voltage; (iii) where when the DC bus voltage is greater than the sum of the driving voltage and the first reference voltage, generating a first output current; (iv) where when the DC bus voltage is greater than the driving voltage and less than the sum of the driving voltage and the first reference voltage, generating a second output current; and (v) matching an average current of the first output current and the second output current with a corresponding driving current.