A multicore fiber for communication 10 which allows propagation of an optical signal includes: a clad 12; a core 11a which is arranged in a center of the clad 12; and seven to ten cores 11b which are arranged at equal intervals surrounding the core 11a, and the cladding diameter is 230 μm, distances between centers of the mutually neighboring cores 11a and 11b are 30 μm or more, distances between the centers of the cores 11b and an outer peripheral surface of the clad 12 are 35 μm or more and a mode field diameter of light propagating in the cores 11a and 11b is 9 μm to 13 μm.