Abstract: In order to meet the needs of measurement and calibration of the electrical parameter test system of the aircraft power test bench, the reference voltage signal source for calibrating the electrical parameter test system of the aircraft power test bench with STM32 as the core is developed. The reference voltage signal source can output the voltage signal which has high-precision and adjustable amplitude with a range of ±10 V, a minimum step size of 0.019 mV, and a quantization error of 9.5 μV. The experimental test results show that the reference voltage source can output signals which can meet all the calibration requirements of the amplitude, the period duration and the waveform parameters. The calibration equipment composed of the reference voltage signal source can not only meet the measurement calibration requirements of the accuracy and traceability of the measurement results of the electrical parameter test system of the aircraft power test bench, but also can greatly improve the calibration efficiency of the electrical parameter test system of the aircraft power test bench.