Optical fibers 301-308 are housed in V-grooves formed on a V-block 20 with end faces 311-318 flush with an end face 22 of the V-block 20. Therefore, when the optical fibers 301-308 are connected to optical waveguides, the V-block 20 suppresses the oscillation of the end faces 311-318 of the optical fibers 301-308. This structure increases the alignment precision and increases the intensity of the optical fibers 301-308.