Disclosed herein are a circuit and a method for driving LED light. There is provided a circuit for driving LED light, including: a dimming block comparing line voltage supplied to the LED light with reference voltage to output a peak value of voltage charged according to a comparison signal as a first reference signal; a reference signal generation block comparing the first reference signal output from the dimming block with a peak value of sensing voltage sensing current of an LED driving switch to amplify an error and multiplying the line voltage by the error amplified signal so as to be output as a second reference signal; and a PWM control block comparing the second reference signal output from the reference signal generation block with the sensing voltage to output a PWM signal with controlled duty. In addition, a method for driving LED light is proposed.