An illumination apparatus includes: a light guide that is formed in a rod shape and includes a positioning portion that is formed at one end in a longitudinal direction, and light incident surfaces that are formed at two end faces in the longitudinal direction; and light sources that are arranged in the vicinity of the light incident surfaces, respectively, and that emit light that is incident on the incident surfaces. The light guide is formed by injection molding. A gate portion for supplying a resin material during injection molding opens at a position that corresponds to a tip face of the positioning portion.