Abstract: A marker light comprising first and second reflectors each having a focus, a reflection surface of a quadric of rotation, an opening at the vertex end and a light projecting opening at the other end, the vertex ends of the reflectors facing each other and the focus of the first reflector being positioned closer to the light projecting opening of the first reflector than is the focus of the second reflector, a light source provided between the focuses of the first and second reflectors for emitting light, light from the light source being reflected from the first and second reflectors and supplied through the light projecting openings of the first and second reflectors, and a housing housing the first and second reflectors and the light source and having a first transparent section for passing light reflected from the first reflector and a second transparent section for passing light reflected from the second reflector, the first and second transparent sections being positioned to face the light projecting ope