An inverter circuit control method and a device thereof are provided. In the control method, after determining a DC bus voltage and an output leakage current of a target inverter circuit, a modulation harmonic wave to be injected into a SPWM signal is adjusted according to the DC bus voltage or the output leakage current if it is determined according to the DC bus voltage that the target inverter circuit satisfies a preset modulation condition, such that total harmonic distortion of a current of the target inverter circuit is within a preset range. The DC bus voltage and the output leakage current of the target inverter circuit are used as references for adjusting the modulation harmonic wave, ensuring total harmonic distortion of the current of the target inverter circuit to be within a preset range.