Abstract: The electric energy metering system consists of a watt-hour meter,a voltage transformer and a current transformer.Hence,the errors of an electric energy metering system should emanate from these parts.To achieve measuring accuracy of the power metering system under harmonic conditions,the equivalent circuits of the electronic watt-hour meter,capacitive voltage transformer and electromagnetic current transformer under harmonic conditions are built,and the harmonic measuring/metering errors and the influencing factors are analyzed.A model of the entire electric energy metering system is set up to analyze its errors under harmonic conditions.By analyzing and simulating an electric energy metering system,the economic influence of harmonics on the metering system is studied,providing a theoretical basis for quantitative analysis of measuring error in an energy metering system under harmonics.