An electronic device integrity monitoring apparatus (2, 2a, 1b) for monitoring the integrity of an electronic device that outputs a control signal to an operating device whose operation is to be controlled, the apparatus (2, 2a, 1b) comprising: a control unit with which the electronic device is provided, capable of generating the control signal; a monitoring unit with which the electronic device is provided, capable of monitoring a state of the control unit by performing the same calculation as that performed by the control unit; a storage unit (24, 27, 24a, 24b) capable of storing a first reference value serving as a reference value of a voltage value or a current value of an input/output electric signal that is input into or output from the control unit and a second reference value serving as a reference value of a voltage value or a current value of an input / output electric signal that is input into or output from the monitoring unit; a first caution signal output unit (25, 25a) capable of comparing said input / output electric signal that is input into or output from the control unit with the first reference value stored in the storage unit (24, 24a, 24b), capable of calculating an amount of deviation therebetween, and capable of outputting if the amount of deviation exceeds a predetermined first threshold value, a first caution signal for signaling that degradation of the control unit has been detected; and a second caution signal output unit (28, 28a, 28b) capable of comparing said input / output electric signal into or from the monitoring unit with the second reference value stored in the storage unit (27, 24a, 24b), capable of calculating an amount of deviation therebetween, and capable of outputting if the amount of deviation exceeds a predetermined second threshold value, a second caution signal for signaling that degradation of the monitoring unit has been detected, characterized in that the first reference value and the second reference value are acquired and stored in the storage unit (24, 27, 24a, 24b) at the timing of the pre-flight check performed for the first time since the actuator control system had been mounted to the aircraft, and the first caution signal output unit (25, 25a, 25b) and the second caution signal output unit (28, 28a, 28b) capable of acquiring the input/output electric signals into/from the control unit and the monitoring unit, respectively, at the timing of each pre-flight check that is performed before every take-off. a control unit with which the electronic device is provided, capable of generating the control signal; a monitoring unit with which the electronic device is provided, capable of monitoring a state of the control unit by performing the same calculation as that performed by the control unit; a storage unit (24, 27, 24a, 24b) capable of storing a first reference value serving as a reference value of a voltage value or a current value of an input/output electric signal that is input into or output from the control unit and a second reference value serving as a reference value of a voltage value or a current value of an input / output electric signal that is input into or output from the monitoring unit; a first caution signal output unit (25, 25a) capable of comparing said input / output electric signal that is input into or output from the control unit with the first reference value stored in the storage unit (24, 24a, 24b), capable of calculating an amount of deviation therebetween, and capable of outputting if the amount of deviation exceeds a predetermined first threshold value, a first caution signal for signaling that degradation of the control unit has been detected; and a second caution signal output unit (28, 28a, 28b) capable of comparing said input / output electric signal into or from the monitoring unit with the second reference value stored in the storage unit (27, 24a, 24b), capable of calculating an amount of deviation therebetween, and capable of outputting if the amount of deviation exceeds a predetermined second threshold value, a second caution signal for signaling that degradation of the monitoring unit has been detected, characterized in that the first reference value and the second reference value are acquired and stored in the storage unit (24, 27, 24a, 24b) at the timing of the pre-flight check performed for the first time since the actuator control system had been mounted to the aircraft, and the first caution signal output unit (25, 25a, 25b) and the second caution signal output unit (28, 28a, 28b) capable of acquiring the input/output electric signals into/from the control unit and the monitoring unit, respectively, at the timing of each pre-flight check that is performed before every take-off.