An apparatus for driving an LED includes a power conversion module and a protection module. The power conversion module shifts the potential of an input voltage upward or downward according to a duty cycle of a PWM signal, and outputs a driving signal to drive the LED. In addition, the protection module determines a state of a protection signal to control the operation of the power conversion module according to the potential of the driving signal. When the potential of the driving is greater than a first preset value and smaller than a second preset value, the power conversion module is controlled to stop outputting the driving signal. When the potential of the driving signal is not greater than the first preset value and not smaller than the second preset value, the power conversion module is controlled operating normally.