The fluorescent lamp retaining member retains two lamp units each including two fluorescent lamps that have electrodes at both ends thereof, a bundling member that bundles a wire from each of electrodes at one end of the two fluorescent lamps, and a conductive member that connects electrodes at the other end of the two fluorescent lamps through a conductive path. The fluorescent lamp retaining member holds the vicinity of the central of each of the fluorescent lamps so arranged in parallel as to set the bundling members in the same direction. The fluorescent lamp retaining member allows one retained lamp unit to rotate relative to the other retained lamp unit adjacent thereto, and so retains the lamp units adjacent to each other that the bundling members and conductive members are arranged alternately after one lamp unit has been rotated.