A liquid crystal display (LCD) including a LCD panel having a plurality of pixels, a source driver outputting a plurality of pixel voltages to the LCD panel, a gate driver, and a timing controller is provided. During performing a polarity inversion on a polarity signal corresponding to a first frame, the timing controller sequentially outputs a first start signal and a second start signal to the gate driver in a first frame period corresponding to the first frame. The gate driver sequentially outputs a plurality of first scan signals and a plurality of second scan signals to the LCD panel according to the first start signal and the second start signal, so that the brightness corresponding to a plurality of gray levels in the first frame are equal to the brightness corresponding to the gray levels in a plurality of previous frames and a plurality of following frames.