To improve a lighting unit with a uniform lighting action that can be manufactured at a comparatively low cost and that costs less to maintain than required.

In a lighting unit of a form consisting of an optical waveguide element having a curved, extending, and slender light-emitting surface and at least one light source for causing the optical waveguide element to emit light, an optical waveguide element 2 has an input joining section 3 for at least one light source. Through the input joining section, most of light is adapted to be incident approximately parallel to the light-emitting surface 6. The optical waveguide element 2 is configured to further reflect at least a part of incident light along the curved light-emitting surface by total reflection. In addition, in either way, there is provided a reflection means for output-joining a definable part of further reflected light to the light-emitting surface.