Liquid crystal display (LCD) device and driving method thereof

The invention provides a liquid crystal display (LCD) device and a driving method thereof. The LCD device comprises an LCD panel, a data driving circuit, a public voltage generation circuit and a scanning and driving circuit, wherein the LCD panel comprises a plurality of data wires, a plurality of scanning wires intersected with the data wires and a plurality of public electrodes; the scanning and driving circuit is used for adding a series of scanning signals to the scanning wires; the public voltage generation circuit is used for providing public voltage to the public electrodes; and the data driving circuit is used for adding a plurality of gray-scale voltage signals corresponding to the public voltage to the data wires when the LCD panel is scaned. The public voltage is a pulse signal which takes at least two frames as a cycle, and the pulse signal changes cyclically in each frame. The public voltage in one cycle comprises at least two different pulse signal cycles. The LCD device can improve the phenome