PURPOSE: To improve assemblability by locking a shelf support to both edges of the front and rear crosspieces of a rear shelf and forming a guide groove that is provided continuously with a guide projection formed in one piece from a rib for supporting shelf supported and guided in one piece with the shelf support.

CONSTITUTION: A front shelf 3 and a rear shelf 4 are subjected to spot welding and a coating treatment separately, the front shelf 3 is arranged at a lower part, a rear crosspiece 3b of the front shelf 3 is arranged at the upper portion of a guide groove 5c of a shelf support 5, and holes 5a and 5b of the shelf support are pressed into front and rear crosspieces 4a and 4b of the rear shelf 4 for engagement, thus assembling a shelf device where the front and rear shelves 3 and 4 are formed in one piece. Then, by utilizing the guide groove 5c and a guide projection 7b that is formed in one piece by a rib 7a for supporting shelf, the front shelf 3 is slid to the rear shelf 4 for supporting and at the same time an inexpensive shelf device that can be rotated freely by a rotary shaft 5f formed in one piece with the shelf support 5 and has an improved assembling property can be obtained.