The present invention is a control device of a motor, for drawing out a capacity of the motor as much as possible so as to achieve a high-speed high-output performance thereof while securing a stability, including: a converter unit configured to rectify and smooth an AC voltage, and to output a DC main circuit voltage; an inverter unit configured to pass a current for driving the motor, with the use of the main circuit voltage; a current detector configured to detect an armature current passing through the motor; a position detector disposed on the motor, the position detector being configured to detect a motor speed; and a current control unit configured to control, upon reception of a q-axis current command (Iqr), the armature current passing through the motor, by outputting a signal for driving the inverter unit, with the use of data from the current detector and data from the position detector.