A display device includes an image signal processing unit to output a high-speed image signal with the aid of an image interpolation unit outputting a low-speed image signal. The display device includes an image signal processing unit to receive a primitive image signal having a first frequency and to output a 4× image signal having a second frequency. The second frequency is four times the first frequency. The display device includes a display panel displaying an image corresponding to the 4× image signal. The primitive image signal includes an (n−1)-th frame (where n is a natural number) and an n-th frame. The image signal processing unit includes a first image interpolation unit and second image interpolation unit, which receive the (n−1)-th frame and the n-th frame and output a 2× image signal including at least one interpolated frame.