The present invention provides a LCD display device, which comprises an image input interface, an image processing unit, a LCD, and a backlight source, wherein, the backlight source is divided into at least two backlight source zones, and each backlight source zone comprises a LED driver; the image processing unit comprises an image analysis unit, a zoning unit, a backlight source driver, and a central processing unit; the backlight source driver comprises at least a MCU, and the MCU allocates a data register and a register address for the LED driver that driven by it; the central processing unit writes the backlight brightness correction value for each backlight source zone into the data register of the corresponding MCU; the MCU produces an appropriate driving signal for the corresponding LED driver. The LCD display device provided in the present invention controls the backlight source drivers in a serial mode, and thereby can reduce the cost and the size of the backlight source.