To accurately detect a fault without newly installing a fault detection sensor in addition to a control sensor.

In the motor control device which controls a DC motor on the basis of a detection value of a stroke sensor 7 for detecting the operation state of an output shaft 14 driven by the DC motor 15, the motor control device includes: a voltage detector 31 which detects an inter-terminal voltage of the DC motor 15; a current detector 32 which detects a current of the DC motor; a motor rotation speed estimation part 33 which estimates the number of revolutions of the DC motor on the basis of detection values of the voltage detected by the voltage detector and the current detected by the current detector; and a fault determination part 34 which determines the faults of the DC motor and the stroke sensor on the basis of the detection value detected by the stroke sensor and the estimation value estimated by the motor rotation speed estimation part.