Summary：

This invention provides a lithium-sulfur battery electrolyte containing fluorinated ketone-based additive and lithium-sulfur battery comprising the electrolyte. The electrolyte comprises a lithium salt, an ether-based solvent, and a specific type of fluorinated ketone compound as an additive. The electrolyte of this invention can significantly improve the performance of a lithium-sulfur battery by adding only a small amount of a specific type of fluorinated ketone compound, and can save the cost of preparation.