Abstract: A non-aqueous electrolyte of a lithium-ion battery and a lithium-ion battery. The non-aqueous electrolyte of the lithium-ion battery comprises a non-aqueous organic solvent, a lithium salt, and an additive. The additive comprises unsaturated phosphate as illustrated in the following structural formula (A) and lithium difluorophosphate, wherein in formula (A), R1 and R2 are independently selected from C2-C5 unsaturated hydrocarbyl groups, and R3 is one of C1-C6 saturated hydrocarbyl groups, C1-C6 unsaturated hydrocarbyl groups, and fluorinated hydrocarbyl groups. In the non-aqueous electrolyte of the lithium-ion battery, a combination of lithium difluorophosphate and unsaturated phosphate at least containing two unsaturated groups can reduce impedance of the lithium-ion battery and further improve high-temperature performance of the battery, so that the lithium-ion battery has better low-temperature performance and high-temperature cycling performance.