A plurality of optical fiber groups are housed in an optical fiber cable and which of the optical fiber groups optical fibers, which constitute the optical fiber groups, belong to can be identified depending on a covering of the optical fibers. Each of optical connectors (plug, receptacle) which are respectively attached to both ends of the optical fiber cable has regions, in which insertion holes in which the optical fibers are inserted and fixed one by one are formed to be arranged in a predetermined interval, in the same number as the number of the optical fiber groups, and even though the optical fibers in one optical fiber group are inserted and fixed in the insertion holes in an identical region, an arrangement order of the optical fibers in the region of the optical connector provided on one end is not maintained as an arrangement order of the optical fibers in the region of the optical connector provided on the other end.