To provide a tunnel luminaire and illumination system that can be used instead of or together with a photocatalyst film, and is used to prevent dirt f from adhering.

The adhesion of dirt is prevented by keeping the temperature of a translucent cover 2 not less tan 50°C. A sheathed heater used as a heating means is installed in a luminaire space. A swirl due to the traffic of automobiles is produced in a one-way tunnel. Since the adhesion of dirt is increased if a light source translucent cover 2 is located in the vicinity of the starting point of the swirl, the adhesion of dirt is decreased by placing a lighting control part 7 at that position, and placing a light source lamp 5 and a reflector 6 on the side in the exiting direction of automobiles. The temperature of the translucent cover 2 can be kept high by controlling multiple tunnel luminaries installed in the tunnel and lighting them mixing with modulated light all day long, so that the adhesion of dirt to the translucent cover 2 is reduced.