The present application relates to an electrolytic solution and an electrochemical device using same. The electrolytic solution of the present application comprises a compound containing a —CN functional group and a compound containing a P—O bond. By introducing the compound containing a —CN functional group and the compound containing a P—O bond into the electrolytic solution, an active material can be better protected, thereby effectively improving floatation performance and nailing performance of a battery, and cycle impedance of the battery.