To provide a panel fixing structure in which a cap piece for covering the upper end of a panel and a fixing structure is reduced in thickness by reducing the size the fixing structure at the upper end of the panel.

The first contact piece 13 of a horizontal member 6 is brought into contact with one surface 2a of a panel 2 in the thickness direction, and the second contact piece 21 of a fixing member 7 is brought into contact with the other surface 2b of the panel 2 in the thickness direction. The panel 2 is held by the horizontal member 6 and the fixing member 7 by connecting the horizontal member 6 and the fixing member 7 by a connection mechanism 8 to fix the panel 2. The connection mechanism 8 connects the horizontal member 6 and the fixing member 7 in the vertical direction perpendicular to the thickness direction. Therefore, a space for extending a bolt for connecting the horizontal member 6 and the fixing member 7 does not need to be secured above the upper end of the panel 2 in the thickness direction of the panel 2. Consequently, the size of the gap A1 can be reduced.