PURPOSE: To facilitate the connection of a wall panel and a ceiling panel.

CONSTITUTION: Insertion legs 7a, 7a of a connecting member 7 provided with the insertion leg 7a having a coupling projection 7f, a contact plate section 7b horizontally formed at the upper end of 7a, a rise section 7c rising from the contact plate section 7b, and a claw section 7e protruded slantly downward from the upper end of the rise section 7c are inserted into the vertical pipe 15 of a tile panel 11 from above. The coupling projection 7f is inserted into a hook hole 15a, a ceiling panel 8 is mounted on the contact plate section 7b of the connecting member 7 via a cushion material 10, the upper end of the end edge section 8b of the ceiling panel 8 is brought into contact with the claw section 7e of the connecting member 7, and the ceiling panel 8 is fixed.