A head mounted display comprising: a display device 2 at the front; a front frame 12 surrounding the forehead; a back frame 14 surrounding the back portion of the head; connecting devices 30A and 30B for connecting the front frame 12 and the back frame 14 in a manner freely movable toward the back and front of the head; belts 16A and 16B placed on the inner surface of both the front frame 12 and the back frame 14 and around the temples; and a belt fastening and loosening device 20 for fastening the belts 16A and 16B and for releasing the fastened belts.
