A driving device for a display device and a method of compensating an image signal of the display device in which the driving device for a display device having a plurality of pixels includes: a first compensating unit that converts an image signal corresponding to the pixel into a first compensated signal according to a difference between the image signal, and an image signal in a previous frame; a second compensating unit that converts the first compensated signal corresponding to the pixel into first and output image signals; an edge detecting unit that outputs a signal according to whether the pixel exists in an edge region in an image based on a difference between image signals corresponding to peripheral pixels; and a first calculating unit that generates converted signals of the first and second output signals based on the output signal of the edge detecting unit.