To connect a vertical panel such as a wall panel and a horizontal panel such as an L-shaped panel and a ceiling panel simply at the original places of installation without using a special attachment even at a position, where there is a ceiling beam and even at a position, where there is no ceiling beam.

A guide groove 3, in which one end section has an inserting hole 3A having broad width and which has a slot 3B having narrow width extending over the other end section from the inserting hole 3A, is formed to a horizontal panel 1, and a tapered link pin 4 is projected and fitted at the upper end of a vertical panel 2. The head section of the tapered link pin 4 has size, in which the head section is inserted into the inserting hole 3A of the guide groove 3 but it is not inserted into the slot 3B, while the diameter of a straight section in the lower section of a tapered section is formed in size slightly smaller than the width of the slot 3B. The lower section of the tapered section is press-contacted from the upper section of the slot 3B by inserting the tapered link pin 4 into the inserting hole 3A of the guide groove 3, moving the horizontal panel 1 and shifting the tapered link pin 4 up to the other end section of the slot 3B of the guide groove 3, the straight section is fitted, and the horizontal panel 1 is connected so as not to be floated from the vertical panel 2.