The present invention relates to a non-aqueous electrolyte solution for a lithium secondary battery, comprising sulfolane-based additives. The non-aqueous electrolyte solution for a lithium secondary battery according to the present invention comprises: an ionizable lithium salt; an organic solvent; and a sulfolane compound expressed by the following chemical formula 1, wherein the content of the sulfolane compound is 0.1 to 5 parts by weight with respect to the sum 100 parts by weight of the lithium salt and the organic solvent. The non-aqueous electrolyte solution for a lithium secondary battery according to the present invention may maintain a low-temperature output at an excellent level and simultaneously may exhibit superior high-temperature storage performance and improved cycle life.