A folding hat that eliminates the risk of damaging the cloth by an elastic ring for a long life. The folding hat has the elastic ring sewn in an outer circumferential edge of a brim, and the elastic ring is formed by coupling both ends of a flat wire rod shaped by rolling spring steel round wire. Regarding the elastic ring, both ends of the flat wire rod are preferably coupled by: inserting both ends of the flat wire rod in both sides of a tubular metal stop, respectively; and crushing the metal stop. The metal stop has a pair of facing convex parts on which the tips of both ends of the flat wire rod can respectively abut at an inner center part that may be used.