A manipulator-device controlling method of the present invention includes: a step (SA1) of receiving manipulation signals for manipulators； a step (SA2) of calculating a target position of a joint on the basis of the manipulation signals； steps (SA3, SA4, and SA5) of calculating a maximum distance between the manipulators when the joint is assumed to be placed at the target position； a step (SA6) of comparing the maximum distance with a predetermined threshold； a step (SA7) of moving the joint to the target position in the case in which the maximum distance is equal to or less than the predetermined threshold； and a step (SA8) of stopping the movement of the joint in the case in which the maximum distance is greater than the predetermined threshold.
