Embodiments of the present disclosure relate to a method for compensating brightness unevenness of a display device. In an embodiment of the present disclosure, a display device includes a display screen, a data driving circuit, and a mainboard. The method for compensating brightness unevenness according to an embodiment of the present disclosure includes obtaining, by the data driving circuit, first brightness compensation data from the mainboard. Then, the data driving circuit adjusts image data according to the first brightness compensation data.