In order to calibrate the crest factor of the aircraft power supply characteristic test system, and to ensure the accuracy of the test results of the system, the programmable power supply and related hardware equipment were used to generate the specified crest factor. By analyzing and studying the common methods of time domain and frequency domain for generating AC voltage signals with specified crest factor, a parabolic fitting method was proposed to generate AC voltage signals with specified crest factor. Through the actual measurement analysis, it is verified that the parabolic fitting method has higher accuracy, and is more suitable for calibrating the crest factor of the aircraft power supply characteristic test system.