Fabrication of an ultrahigh density cable is important, especially for subscriber loops. By using ultrahigh density cable, low cost optical transmission lines may be constructed. A multicore optical fiber1 100-200 μm in diameter is suitable. By using multicore fiber the cable diameter can be reduced drastically, compared with using ordinary monocore fiber. However ordinary multicore fiber is difficult to splice, because due to its circular construction, it is difficult to determine proper alignment. Splicing is difficult because the fibers must be rotated to achieve proper alignment. To overcome this, we developed a more easily spliced multicore fiber: bunch fiber.