A display device includes a substrate, a display panel including a first display area, a second display area, and a third display area between the first and second display areas, each of the first, second, and third display areas including a plurality of pixels, and a sensor which is between the substrate and the first display area of the display panel and senses an external object through the first display area. A first pixel density of the first display area is less than a second pixel density of the second display area, and a pixel density of the third display area varies with relative distances from the first display area.