A lithium ion secondary battery that can inhibit an electrolytic solution in the lithium ion secondary battery using a negative electrode active material containing Si from decomposing, improve cycle characteristics, and obtain both a high energy density and a longer service life. A lithium ion secondary battery contains a negative electrode, a positive electrode, a separator installed between the negative and positive electrodes, and an electrolytic solution; the electrolytic solution contains fluoroethylene carbonate; the negative electrode has a negative electrode active material having particles containing silicon and particles containing carbon and a film being formed over a surface of the negative electrode active material and containing fluorine; and a surface area of the particles containing silicon and a content of fluorine contained in the film satisfy the following Formula 1: 0.005 g/m2≤(Fluorine content (g) contained in film)/(Surface area (m2) of particles containing silicon)≤0.015 g/m2.