The present invention discloses a gel mat and a method for manufacturing the same. The purpose thereof is to provide a gel mat which features simple manufacturing process, low cost, ease of use, high reliability, and freedom from possible damage in case of being pierced or depressed with a pressure, and a method for manufacturing the same. The gel mat includes a hermetically sealed bag which is constituted by two layers of a film material, the bag being packed with gel flakes. Said method for manufacturing a gel mat comprises the steps of preparation of material, bag making, monomer solution pouring, heating for solidification, and inspection and packaging in this order. The present invention adopts a gel instead of water, which is conventionally used, for producing a flake gel mat the external surfaces of which are inside a bag; the gel is a colloid obtained by polymerizing the organic matter; approx. 70% of the gel is constituted by water; and thus the gel mat has an extremely good endothermic performance. In addition, the gel offers no flowability like water, being able to be stably used, and even when the bag is broken through by a pointed substance or burst out to be holed, there will cause no leakage, which allows the service life of the mat to be substantially extended. The method for manufacturing uses polymerization reaction; smoothes the gel mat flat inside the bag by applying an external pressure; and thus can provide a finished gel mat which has smooth and neat outer surfaces.