Provided is an optical unit capable of preventing unintended light distribution and having a small assembly error while using a plurality of light sources and a plurality of lenses. An optical unit (10) includes: a plurality of light sources (26); a plurality of first lenses (30) integrally formed, respectively arranged to correspond to each of the light sources (26), condensing light from the corresponding light sources (26), and forming corresponding light source images on a predetermined virtual plane; a second lens (12) projecting projected images of the light source images forward; and a light-shielding member (31) extending between two adjacent first lenses (30) in the first lenses (30), and shielding light passing through one first lens (30) so as not to enter the other first lens (30), in which the light-shielding member (31) and the first lenses (30) are integrally formed by two-color molding.