An exemplary embodiment of method of establishing a gamma table using a system includes following steps. Providing a signal generator, a display device, and a color analyzer, consists of measuring luminance values of the images corresponding to a plurality of reference sampling points. Obtaining a luminance characteristic curve based on the reference sampling points and luminance values using Bezier curve interpolation. Locating the gray scales on the luminance characteristic curve with the same luminance values as the gray scales of a standard gamma table. And establishing a gamma table by comparing the gray scales of the standard gamma curve and the luminance characteristic curve.