To improve the installation work by enabling a lamp body part to be temporarily held to a support member.

In a lighting system, which has a lamp body part 1 with a mounting part 1a in the form of a downwardly open cylinder and a support member 2 formed into a stepped cylindrical shape being open upwards and having a large diameter part 2d joined to the underside of a small diameter part 2c via a step 2e, and which is mounted by fitting the mounting part 1a over the small diameter part 2c, one end of a hanging member 4 is connected to the lamp body part 1 by passing the hanging member 4 through the mounting part 1a, and a stopper 5 which can be passed through the small diameter part 2c of the support member 2 and which is large enough to be locked near the step 2e inside the large diameter part 2d by raising the hanging member 4 after passing the stopper through the small diameter part 2c is connected to the other end of the hanging member 4.