To provide a luminaire requiring no fixture such as a rivet or a screw in which its shade body can be assembled easily and simply, in the luminaire having such a structure as joining the end portions of side plates to assemble the shade body.

In this luminaire, small side plates 1a to 1e adjoining via perforated folding line 2 boundaries are folded into cylinder-like, and both end portions thereof are connected and assembled into a shade body 5 in which a lamp is mounted. An L-shaped engage piece 3 is formed on the left end portion of the small side plate 1a, and a slit-like engage hole 4 capable of engaging with the engage piece 3 is formed on the right end portion of the small side plate 1e. By engaging the engage piece 3 with the engage hole 4 the left end portion of the small side plate la and the right end portion of the small side plate 1e are connected mutually so that the shade body 5 is assembled.