A display device includes: a display unit including a first display area and a second display area; and a data driver configured to supply a data signal to the display unit, wherein the data driver includes: a data signal generator configured to generate the data signal in response to input data; a first buffer unit and a second buffer unit configured to supply the data signal from the data signal generator to the first display area and the second display area, respectively, and to be turned off during a non-display period of a corresponding display area; and a sub driver configured to supply a black data signal to the first or second display area during the non-display period of the corresponding display area.