In view of suppressing gas production during storage at high temperatures and during charge and discharge cycles while ensuring favorable low-temperature characteristics, the invention aims to provide a non-aqueous electrolyte in which the proportion of diethyl carbonate is reduced, and a non-aqueous electrolyte secondary battery using the same that has high safety. The non-aqueous electrolyte of the invention for use in secondary batteries includes ethylene carbonate, propylene carbonate, diethyl carbonate, and an additive, as a non-aqueous solvent. The additive is at least one of a fluorinated aromatic compound having a molecular weight of 90 to 200 and a fatty acid alkyl ester having a molecular weight of 80 to 240. A weight ratio WEC of ethylene carbonate, a weight ratio WPC of propylene carbonate, a weight ratio WDEC of diethyl carbonate, and a weight ratio WLV of the additive are 5 to 30 wt %, 15 to 60 wt %, 10 to 50 wt %, and 5 to 35 wt %, respectively, to the total of the non-aqueous electrolyte.