A luminance correction system includes an image pickup device configured to pick up a test image and generate pickup data, a parameter calculation device configured to calculate a first target luminance that is a maximum luminance of a reference area in a display panel and a detected maximum luminance that is a luminance of a correction target sub-pixel based on the pickup data with respect to a maximum grayscale, determine a second target luminance by correcting the first target luminance, and calculate correction parameters, and a display device including the display panel, the display device configured to compensate the input grayscale of the correction target sub-pixel to a target grayscale based on the correction parameters and generate a data voltage by adjusting upward a gamma voltage corresponding to the target grayscale.