PURPOSE: To easily form a disk connected in a transverse direction of a top plate facing type by using a box-shaped frame base body which is internally hollow as a base and attaching and detaching the supporting frames of top plates and beam members to serve as leg members at the front and rear of the base body.

CONSTITUTION: The desk edge top plate 9 is removed and cap members 7 mounted hitherto in the apertures in mounting parts 3e to 3h at four points on the front surface side of the frame base body 1 of the disk are removed in order to form the desk in the connecting state in the transverse direction. The upper beam members and the lower beam members are mounted and fixed to the mounting parts 3e to 3h after removal and the top plate 6 is placed and fixed atop the upper beam members. Consequently, the connecting form in the face-to-face state of the desks is formable by mounting the upper and lower beam members 4d, 5d to the front surface side of the box-shaped frame base body 1 and placing and fixing the top plate 6 on the front end of the upper beam members 4d and the box-shaped frame base body 1 as the desk of the independent min. unit. Then, the desks are formed on both the front and rear surfaces of one piece of the box-shaped frame base body 1.