An object of the present invention is to provide an electric double layer capacitor which has a high withstand voltage, and is resistant to degradation and excellent in long term reliability. Disclosed is an electrolytic solution for an electric double layer capacitor including a solvent (I) for dissolving an electrolyte salt and an electrolyte salt (II), wherein the solvent (I) for dissolving an electrolyte salt includes a sulfolane compound and a fluorine-containing chain ether. Also disclosed is an electric double layer capacitor using the electrolytic solution.