A pressure regulating valve is provided on a terminal plate of a capacitor. This pressure regulating valve includes a gas permeable sheet, a valve body made of silicone rubber, a packing, and a cap. The gas permeable sheet that prevents permeation of electrolyte is provided so as to close a hole created in the terminal plate. The packing is interposed between the valve body and the gas permeable sheet, and is made of an elastic material with moisture permeation resistance higher than that of silicone rubber. The cap is fixed onto the terminal plate and covers the valve body and the packing such that the valve body and the packing are retained in a compressed state with respect to the terminal plate. The valve body and the packing are provided away from the gas permeable sheet.