A display system with high display quality in which display unevenness is reduced is provided. The display system includes a processing unit and a display portion. The processing unit generates second image data by using first image data. The display portion displays an image on the basis of the second image data. The processing unit includes three layers. The first image data is supplied to the first layer. The first image data contains a plurality of pieces of data. The plurality of pieces of data each correspond to any one of the plurality of pixels. The first layer generates first arithmetic data by making the number of data corresponding to one pixel larger than the number of the first image data by using the first image data. The second layer generates second arithmetic data by multiplying the first arithmetic data by a weight coefficient. The third layer generates the second image data by making the number of data corresponding to one pixel smaller than the number of the second arithmetic data by using the second arithmetic data.