A display device is disclosed. The display device includes a display panel, a backlight module, and a processor. The display panel displays a display screen. The backlight module provides a backlight brightness to the display panel. The processor generates the display screen and determines the backlight brightness corresponding to the display screen. The processor dynamically adjusts a size and a position of several display areas on the display screen based on an instant state of the continuous image signal respectively. The processor determines several backlight areas corresponding to several display areas respectively, and the processor generates several backlight control signals corresponding to several backlight areas respectively based on the display setting and several image contents.