A lithium ion secondary battery having excellent durability is provided. The lithium ion secondary battery includes: a positive electrode including a current collector made from aluminum; a negative electrode; and an electrolytic solution. The electrolytic solution contains an electrolyte including a lithium salt, and a linear carbonate represented by formula (2), the linear carbonate is contained at a mole ratio of 3 to 6 relative to the lithium salt, and the electrolyte includes a first lithium salt represented by formula (1) and a second alkali metal salt; (R1X1)(R2SO2)NLi: formula (1); and R20OCOOR21: formula (2).