To provide a desk with a new structure, where the use states of a wiring duct are changed based on a simple principle.

The desk includes a wiring duct space S and a modesty panel 2 in the lower part on the opposite side 3c of the use side of the top board 3. The modesty panel 2 is vertically switched in the upper edge position without changing the depth position with respect to leg bodies 1 for supporting the top board 3. Thus, the desk is constituted to selectively obtain the states in the wiring duct space S, i.e., the first use state S1 clogged by a rising wall 42 to function with the opposite side 3c of the use side as the modesty panel, and the second use state S2 opened without being blocked by the rising wall 42 to function with the opposite side 3c of the use side as the modesty panel. Consequently, the wiring duct can be adapted to the change of the use states by suppressing the number of components and with only a simple work.