An LCD and a display panel thereof are provided. A common voltage generation circuit of the display panel is electrically connected to at least one pixel in a non-active pixels region. According to the display voltage at a drain of a TFT in the pixel, an average of display voltages of positive and negative polarities is obtained in two frame times. The average value is regarded as a common voltage supplied to every pixel in an active pixel region in the display panel. Thereby, the problem of a drift of a feed-through voltage (ΔVD) of a scan voltage due to an RC delay of a parasitic-capacitance and a parasitic-resistance on the scan line can be avoided. Further, the gray-level accuracy of every pixel in the active pixel region can be improved, and the flicker-noise of the display-panel can be reduced, thus significantly promoting the display quality of the LCD.