In order to meet the needs of calibration and verification of AC voltage parameters, a high precision AC voltage standard source circuit is designed in this paper. Based on the requirements of high precision and high stability, the overall circuit adopts a closed-loop feedback structure, uses AD9850 chip to generate AC signal, and then modulates the amplitude of the sine wave through the DC reference voltage. The microcontroller of the circuit uses AVR chip. At the same time, the signal analog circuit and the digital control circuit are electrically isolated, and the accuracy is improved through hardware selection, software compensation and other measures. The output range of the designed circuit is 1~10 V, and the output frequency band is 40 Hz~100 kHz. The AC voltage standard source is repeatedly measured at typical frequency points. The results show that the permissible error of the output full-scale voltage is less than 0.006% in 40 Hz~50 kHz, the permissible error of the full-scale voltage at 100 kHz is kept within 0.025%. The circuit has the advantages of high precision and good stability.