The invention discloses a signal generating device for power system energized test instrument calibration. The signal generating device includes a signal generator, a reference signal power amplifier, a test signal power amplifier, a selecting switch, a reference voltage output channel, a reference current output channel, a test current output channel, a reference voltage sampling feedback circuit, a reference current sampling feedback circuit and a test current sampling feedback circuit. With the signal generating device adopted, voltage, current and phase signals of all kinds of field equipment can be generated in a simulated manner, and relative dielectric loss measurement can be performed on capacitive equipment effectively, and resistance current measurement can be performed on a metal oxide lightning arrester, and the grounding current of the iron core of a transformer can be measured, and the reliability of field test data can be ensured.