A display device includes: a memory configured to store an over-driving lookup table and previous frame block data generated by block averaging previous frame data; an over-driver configured to obtain current frame data from input image data and to generate over-driving frame data for the current frame data by comparing the previous frame block data and the current frame data with reference to the over-driving lookup table; a data driver configured to generate an over-driven data signal based on the over-driving frame data; and a plurality of pixels configured to display an image based on the over-driven data signal, wherein the over-driver is configured to perform an over-driving based on a size of a block divided for the block averaging.