A non-aqueous electrolyte secondary battery including a positive electrode and a negative electrode each capable of absorbing and desorbing lithium, a separator interposed therebetween, and a non-aqueous electrolyte, wherein the positive electrode includes a positive electrode active material represented by: LiM.sub.1-xL.sub.xO.sub.2 where 0.005.ltoreq.x.ltoreq.0.1 is satisfied, M is at least one selected from the group consisting of Mn, Co and Ni, and L is at least one selected from the group consisting of Mg, Al, Ti, Sr, Zn, B, Ca, Cr, Si, Ga, Sn, P, V, Sb, Nb, Ta, Mo, W, Zr, Y and Fe, and the non-aqueous electrolyte includes a phosphinate compound represented by: ##STR00001## where R.sup.1, R.sup.2 and R.sup.3 are each independently an aryl group, or an alkyl group, an alkenyl group or an alkynyl group each having 1 to 5 carbon atoms.