Provided is a light source unit including a base unit formed on a front surface thereof with a first circuit pattern by irradiating laser light to a resin molded article, and a light emitting element mounted on the base unit and electrically connected to the first circuit pattern. The base unit includes a mounting surface portion directed in a prescribed direction such that the light emitting element is mounted thereon, and a sidewall surface portion connected to the mounting surface portion in a plane intersection state, and the sidewall surface portion is formed as an inclined surface intersecting with the mounting surface portion at an obtuse angle.