To obtain a mounting structure of a commodity information indicator of an open showcase, that allows a client to look at a commodity information easily when the client comes close to a commodity in the showcase to see it, and the commodity information indicator to be easily and neatly attached.

The inside of a casing of an open showcase is kept cool in such a way that an opening at the front side of the showcase is covered with a cold air curtain, blown from an air outlet at the upper part of the casing. An insert rail 18 of a commodity information indicator 19 consists of an upper rail 16 with a downward insert opening 16a and a lower 17 with an upward opening 17a, and is attached on a front wall 10a of a nosing 10 along the overall length of the showcase. A night cover rail 14 attached at the upper part of the nosing 10 is bent along the edge to form a downward indicator insert opening 16a and used as the upper rail 16.