(A) capable of alloy formation with lithium metal and occluding lithium ions, at least one material selected from the releasable metal oxide (hereinafter, referred to as a metal and / or metal oxides.), And (b) a lithium-ion occlusion, the releasable surface coated carbon material a negative electrode 3 containing as an active material, the following equation of the metal and / or metal oxide particles (1):

Roundness = 4πS ^/ L 2 (1)
(Where, S: area of ​​the particle projected image, L: is a circumferential length of a particle projected image.)
The average value of circularity is defined in the negative electrode for a lithium ion secondary battery is disclosed which is characterized in that 0.78 or more. Lithium-ion secondary battery having the electrode has a more improved cycle characteristics.