A display device and display method thereof are provided in the field of image displaying technology. The display device includes: a controller, a display driver and a barrier driver. The controller is configured to send an image frame to the display driver and send a first instruction to the barrier driver. The display driver is configured to drive the display panel to display the image frame on a plurality of display areas which are parallel and distributed at intervals. The barrier driver is configured to turn on the electrodes of the first display barriers in the barrier panel according to the first instruction. The first display barriers are configured to block light when energized. Apart from the first display barriers, second display barriers are configured to allow light to pass through. The display device thus provides a visible range within a preset narrow viewing angle.