The corona-resistance lifetime of insulating material of inverter-fed motors is experimentally studied under different switching frequencies (6 kHz, 12 kHz, 18 kHz) and fundamental frequency (10 Hz, 50 Hz, 100 Hz, 150 Hz, 200 Hz) of space vector pulse width modulated (SVPWM) voltage, and contrast experiment of corona-resistance lifetime under repetitive pulse square wave was carried out. The results show that the lower the switch frequency, the longer the corona-resistance lifetime, but the more the time and dispersion of the corona-resistance lifetime results fluctuate at different fundamental wave frequencies; the higher the switch frequency, the shorter the corona-resistance lifetime, but the smaller the time and dispersion of the corona-resistance lifetime test results fluctuate at different fundamental wave frequencies. The 50% duty cycle repetitive pulse square wave can be used to replace the SVPWM wave to predict the corona-resistance lifetime of inverter-fed motor insulation, the higher the switching frequency, 50% duty cycle repetitive pulse square wave is more accurate in predicting insulation corona-resistance lifetime and dispersion of inverter-fed motor under SVPWM voltage, however, it cannot accurately reflect the statistical characteristics when the switching frequency is low.