An electrolytic solution, for use in an electrolytic capacitor, comprising a solvent and a solute wherein water accounts for 20 to 100% by weight of the solvent and the total solute content is from 1.5 to 44% by weight, and an electrolytic capacitor comprising a capacitor element, a case containing the capacitor element, and a sealant with which the case is sealed, the capacitor element comprising a pair of electrode foils each comprising a dielectric, a separator for isolating the electrode foils from each other, and the above electrolytic solution filled between the electrode foils.