This aims to provide a support (10) comprising a bracket (7) attached to a predetermined structure, and a generally cylindrical holder (6) retained in the bracket (7). This bracket (7) has a receiving hole (112) for accommodating the holder (6). This holder (6) has a first rib (122) erected on a curved outer circumference, and an elastic portion (124) for giving the first rib (122) the degree of freedom for motions in the substantially radial direction. This also aims to provide a lighting unit (20) characterized by comprising a board (2), in which light emitting portions (23) having semiconductor light emitting devices are arrayed on the upper face side along the longitudinal direction, reflector members (3A and 3B) mounted on the side of the upper face of the board and having reflecting portions (34a and 34b) for covering the light emitting units and for reflecting the lights from the light emitting units, and a case member (4) disposed to support the board and the reflector members upward and downward.