Electrolytic solution for lithium secondary batteries and lithium secondary battery including the same

Disclosed are an electrolytic solution for lithium secondary batteries capable of improving lifespan characteristics of a lithium secondary battery under a high voltage condition and a lithium secondary battery including the same. The electrolytic solution may includes a lithium salt, a solvent, and a functional additive. In particular, the functional additive includes a high-voltage additive including a first high-voltage additive, e.g., hexafluoroglutaric anhydride, and a second high-voltage additive, e.g., fluoroethylene carbonate.