Provided is a lithium secondary battery including a positive electrode, a negative electrode, a separator, and a non-aqueous electrolyte, wherein the positive electrode includes a positive electrode active material comprising lithium iron phosphate particles, and the positive electrode has a loading amount of 450 mg/25 cm2 to 740 mg/25 cm2, and the non-aqueous electrolyte includes a lithium salt, an organic solvent, and an additive, wherein the organic solvent includes ethylene carbonate, and dimethyl carbonate, and the dimethyl carbonate is included in 5 vol % to 75 vol % in the organic solvent, and the additive contains vinylene carbonate, and the weight ratio of the vinylene carbonate to the dimethyl carbonate is greater than 0 to 0.2 or less.