A passive-type exercising device and its control device are provided in which accuracy of deriving exercise intensity is improved. The passive-type exercising device includes an exercise assistance mechanism for assisting exercise of a user a load setting value acquisition unit 131 for obtaining a load setting value which is a setting value of a degree that the exercise assistance mechanism assists the users exercise an assistance load value derivation unit 132 for deriving an assistance load value that the exercise assistance mechanism assists the users exercise a sensor value acquisition unit 134 for obtaining a sensor value outputted by a sensor unit 32 provided at the exercise assistance mechanism a combined load value derivation unit 135 for deriving a combined load value which is a combined value of the assistance load value and an effective load value of the users active exercise based on the obtained sensor value and an exercise intensity derivation unit 150 for deriving an exercise intensity indicating the users exercise intensity based on the effective load value computed as a difference between the assistance load value and the combined load value.
