A display device that achieves both high-accuracy sensing by a touch sensor unit and smooth input using the touch sensor unit is provided. The display device includes a display unit and the touch sensor unit. The touch sensor unit performs touch sensing operation at a different timing from display image rewriting by the display unit, whereby the high-accuracy sensing can be achieved. The display unit has a function of rewriting a display image only in a region that needs to be rewritten. In the case where the entire display region is not necessarily rewritten, the time for the sensing operation by the touch sensor unit can be lengthened, whereby the smooth input can be achieved.