A sensitivity identifying device has an operating object device configured to operate when an operation member is moved according to a force applied by a user, an assist force applying device for applying an assist force to movement of the operation member, an operation force parameter detecting device for detecting a value of an operation force parameter, an operation response parameter detecting device for detecting a value of an operation response parameter, a sensitivity identifying information storage section for storing sensitivity identifying information associating a sensitivity index, with a combination of the value of the operation force parameter and the operation response parameter, and a sensitivity determining unit for specifying the sensitivity index based on the combination of the value of the operation force parameter and the operation response parameter, and the sensitivity identifying information, and outputting the sensitivity index.