An inverter control device which controls an output current to a 3-phase AC motor, comprising: a 3-phase/dq-axis conversion unit which converts the output current detected by a current sensor into a dq-axis current; and a gain adjustment unit which adjusts a detection gain of the current sensor for each phase, wherein, in a case where a current value of a secondary harmonic component contained in the dq-axis current is equal to or more than a predetermined threshold, the gain adjustment unit corrects a gain of the current sensor such that the current value of the secondary harmonic component becomes less than the threshold, characterized in that: in a first period, the gain adjustment unit sets a detection gain of a first phase current which is any one phase current of the output currents to a first gain value, wherein, in a second period after the first period elapses, the gain adjustment unit sets the detection gain of the first phase current to a second gain value which is smaller than the first gain value, and wherein the gain adjustment unit switches whether the detection gain of the first phase current to be increased or decreased according to a comparison result between the current value of the secondary harmonic component contained in the dq-axis current in the first period and the current value of the secondary harmonic component contained in the dq-axis current in the second period. a 3-phase/dq-axis conversion unit which converts the output current detected by a current sensor into a dq-axis current; and a gain adjustment unit which adjusts a detection gain of the current sensor for each phase, wherein, in a case where a current value of a secondary harmonic component contained in the dq-axis current is equal to or more than a predetermined threshold, the gain adjustment unit corrects a gain of the current sensor such that the current value of the secondary harmonic component becomes less than the threshold, characterized in that: in a first period, the gain adjustment unit sets a detection gain of a first phase current which is any one phase current of the output currents to a first gain value, wherein, in a second period after the first period elapses, the gain adjustment unit sets the detection gain of the first phase current to a second gain value which is smaller than the first gain value, and wherein the gain adjustment unit switches whether the detection gain of the first phase current to be increased or decreased according to a comparison result between the current value of the secondary harmonic component contained in the dq-axis current in the first period and the current value of the secondary harmonic component contained in the dq-axis current in the second period. in a first period, the gain adjustment unit sets a detection gain of a first phase current which is any one phase current of the output currents to a first gain value, wherein, in a second period after the first period elapses, the gain adjustment unit sets the detection gain of the first phase current to a second gain value which is smaller than the first gain value, and wherein the gain adjustment unit switches whether the detection gain of the first phase current to be increased or decreased according to a comparison result between the current value of the secondary harmonic component contained in the dq-axis current in the first period and the current value of the secondary harmonic component contained in the dq-axis current in the second period.