A nonaqueous solvent in a nonaqueous electrolytic solution in a lithium-ion secondary battery 1 contains propylene carbonate (PC), a first compound expressed by formula (I), and a second compound expressed by formula (II). The content of PC in the nonaqueous solvent is at least 10 volume %. The content X [mass %] of the first compound and the content Y [mass %] of the second compound simultaneously satisfy the conditions represented by expressions (1) and (2) [2.ltoreq.(X+Y).ltoreq.8 (1), 0.01.ltoreq.(Y/X).ltoreq.0.30 (2)]. R.sup.1 to R.sup.6 in formula (I) indicate any of a hydrogen atom and hydrocarbon groups having a carbon number of 1 to 3, whereas R.sup.7 and R.sup.8 in formula (II) indicate any of a hydrogen atom and hydrocarbon groups having a carbon number of 1 to 3. ##STR00001##