A liquid crystal display device includes a display panel, a signal generator, a plurality of wires, and a controller. The display panel has a plurality of pixels. The signal generator supplies data signal to the pixels. The wires connect output ends of the signal generator to input ends of the pixels, respectively. The controller varies voltage waveform corresponding to the data signal at the output ends by varying both a voltage level at a rising edge of the voltage waveform and a voltage level at a falling edge of the voltage waveform.