An image display system has an image display apparatus and a peripheral device that can be mounted on the image display apparatus. The image display apparatus includes a first electrode for electrically connecting the image display apparatus and peripheral device, and the peripheral device includes a second electrode for electrically connecting the image display apparatus and peripheral device. These electrodes are placed so as to have contact with one another when the peripheral device is mounted on the image display apparatus. In addition, the image display system moves the mounting position of the peripheral device on the image display apparatus as appropriate. The system minimizes cables used for electrical connections between the image display apparatus and peripheral devices, makes the apparatus compact and allows adoption of a variety of layouts.