An inverter control device controls the operation of an inverter connected to an electric motor. A switching vector SV is determined as an output switching vector SVo to be supplied to the inverter based on a current deviation of the coil winding of each phase of the electric motor and a switching vector determination table. A keeping time TK is calculated based on a torque and a revolution speed of the electric motor. The counting of a time counting is then initiated. In a high revolution speed (TK>Selection time TS), the control operation for the inverter returns to a start step after the elapse of a certain time period that is set in advance. In a low revolution speed of the electric motor (TK