A digital gamma correction system for detecting a brightness of a liquid crystal panel, and correcting a gamma voltage, based on the detected brightness, includes an offset setter for setting the number of detection gray levels and a first detection area, for the detection of the brightness of the liquid crystal panel, a plurality of brightness detectors for detecting brightness values output from the first detection area for the detection gray levels, a controller for processing the brightness values detected by the brightness detectors, a non-linear interpolation data processor for processing a brightness value supplied from the controller, thereby generating non-linear interpolation data as a brightness variation rate according to the gray levels, a brightness corrector for generating gamma correction data for brightness values obtained by interpolating brightness values detected in a second detection area of another liquid crystal panel for a second number of detection gray levels, based on the non-linear interpolation data, and a memory for storing the gamma correction data generated from the brightness corrector.