An image display system includes: a plurality of image supply devices; and an image display device adapted to display one or more supply images out of supply images supplied from the respective image supply devices, wherein each of the image supply devices includes a display section, and an interface section adapted to display an operating image on the display section, the operating image being used for selecting at least one of the supply images to be displayed by the image display device and designating a layout of the images, and to transmit an instruction by a user via the operating image to the image supply devices.