Provided are an inverter control method and a control device that make a soft start possible, said soft start causing no voltage surge or no current surge and using soft switching. The control methodis used for soft-starting an inverter (2) using soft switching, wherein the inverter (2) is a bridge circuit equipped with at least two upper and lower arms. The solution is obtained by the control method characterized in that a soft start using the soft switching is achieved in such a way that: the phases of gate pulses (G1, G4) to an upper arm switching element (Q1) and a lower arm switching element (Q4) which are paired for current energization are mutually shifted, thereby forming a period during which both gate pulses are overlapped with each other; and the magnitude of the shift is changed, thereby gradually widening the overlapped period that specifies the energization period.