Voltage was one of the important measurement parameters of electric energy meter. The accuracy of traditional voltage measurement mostly depended on hardware performance, and high-precision chips caused a significant increase in system cost. Aiming at the problem of traditional high-precision voltage measurement, a new high-precision voltage measurement method based on time measurement is researched in this paper. The electrical level conversion time was obtained by comparing the high frequency signal with the voltage signal to be measured. Then the time-voltage conversion function was constructed to convert the electrical level time into the voltage measurement value again. The voltage measurement was converted into a time measurement with higher measurement accuracy and simple calculation. Thus, high-precision voltage measurement was realized, and high-precision sampling, conversion and calculation of the voltage signal to be measured were avoided. Finally, a corresponding example was constructed, and the feasibility and effectiveness of the proposed method was verified by example results. The experimental results show that the voltage measurement error is better than 8 μV in 10 kHz frequency condition, and the measurement accuracy is better than 32-bit ADC chip ADS1263, a new solution is provided for high-speed and high-precision voltage measurement.