To provide a lithium secondary battery having an excellent input and output balance, a high capacity, and a long life. A lithium secondary battery comprising: a positive electrode containing a positive electrode active material which is applied to both sides of a positive electrode collector foil and contains a lithium transition metal complex oxide; a negative electrode containing a negative electrode active material which is applied to both sides of a negative electrode collector foil and occludes and releases lithium; and a nonaqueous electrolytic solution containing a lithium salt, wherein there is an SOC region where a specific input power is almost equal to a specific output power in a range of 20 to 40% of state of charge (SOC) of the lithium secondary battery.