An image display system is configured to display an image. An obtaining unit is configured to obtain a surrounding image indicating surroundings of a vehicle. A plurality of detecting units are disposed on the vehicle at different positions and configured to detect an object existing around the vehicle, respectively. If one of the detecting units detects the object, the one of the detecting units is referred to as specific detecting unit. An overlapping unit is configured to overlap an indicator represented in the form of a frame with the surrounding image. The indicator indicates the object and the specific detecting unit which has detected the object. A display unit is configured to display the surrounding image with which the indicator is overlapped.