A display device includes a display panel which displays an image based on input image data, a driving controller which generates a voltage control signal for adjusting a first power voltage applied to the display panel in an (N+M)-th frame based on a maximum grayscale value of the input image data of an N-th frame, where N is a positive integer, and M is a positive integer, and a power voltage generator which senses a power current applied to the display panel in the (N+M)-th frame, generates a second power voltage based on the voltage control signal, and controls a voltage level of the first power voltage based on the second power voltage and a current level of the power current.