The stranded optical cable 10 includes a plurality of stranded multicore optical cables 12 and a cable sheath 16 covering the multicore optical cables 12, each multicore optical cable 12 including at least two of optical units 13 as a pair and a unit sheath 14 covering the optical units 13, each optical unit 13 being formed by bundling a plurality of optical fibers. And, parts of the cable sheath corresponding to both ends of the stranded optical cable 10 are removed to expose the multicore optical cables 12 certain lengths so that the optical connectors 21 are connected to the multicore optical cables 12, respectively.