A demura method for a display panel includes the steps: obtaining brightness data of a display image at a gray scale value; calculating the brightness data of the display image to obtain demura data of the pixel; dividing bits of the demura data of the pixel into first bits and second bits according to a bit length of the pixel, setting an integer gray scale value of the pixel according to the first bits, and setting a mixed gray scale value of the pixel according to the second bits.