According to one embodiment, a display device includes a first substrate, a second substrate, a first electrode, a second electrode, a partition electrode, a luminescent layer and a voltage source. The luminescent layer includes a luminescent material emitting light rays due to an electrochemical oxidation or reduction reaction thereof. The voltage source is configured to generate a driving voltage between the first and second electrodes so as to apply first and second potentials, wherein the first and second potentials are maintained at one and opposite polarities in respect to the reference potential during a predetermined segment period respectively and are periodically reversed, each of the first and second potentials is changed first to second absolute levels during the predetermined segment period, the second absolute potential is determined depending on the gradation of input image data, and the first absolute potential is higher than the second absolute potential.