An object of the present invention is to provide a battery of high capacity that is excellent in storage, load, cycle, and continuous charge characteristics and that reduces gas generation; and a nonaqueous electrolyte for use in the battery.The invention relates to a nonaqueous electrolyte which comprises a nonaqueous organic solvent and a lithium salt dissolved therein, wherein the nonaqueous organic solvent contains at least one compound selected from the group consisting of acid anhydrides and carbonic esters having an unsaturated bond, and at least one compound selected from the group consisting of sulfonic compounds and fluorine-containing aromatic compounds having 9 carbon atoms or less; and a lithium secondary battery employing the same.