To provide a nonaqueous electrolyte secondary battery raising charging voltage to high voltage exceeding 4.2 V and adding an antioxidant in a positive mix in order to efficiently utilize the residual capacity of the positive active material.

In the nonaqueous electrolyte secondary battery in which the maximum voltage in operation is 4.25 V or more per cell, by adding 0.1-2 pts.wt. antioxidant to the positive mix, strong oxidation decomposition in the vicinity of a positive electrode can be prevented even at high charging voltage exceeding 4.2 V, and as a result, theoretically possible efficient utilization of the residual capacity of the positive active material in a positive mix is made possible, and high energy density can be obtained.