To provide a folding eyeglass case foldable and having higher economical efficiency and productivity than a conventional eyeglass case by simplifying the structure, and reducing the number of parts.

The whole body of the folding eyeglass case is composed of a body 1, two side surface parts 2, and a folded part 3. The body 1 is formed as a rectangular sheet on the whole, and two folding lines 11 and 12 parallel to the lateral direction are formed in the body 1 so that the body has a polygonal tube when folded. Each side surface part 2 is to form a side surface in the opening end of the body 1. One side of the side surface part 2 is fixed to the body 1, and a support piece 4 is extended from only one side of sides adjacent to the side of the side surface part 2 fixed to the body 1 and is fixed to the body 1.