This paper proposes a robust motion-tracking control for multilateral systems. The multilateral systems have been proposed as the system of acquiring and transmitting the haptic information between some systems. In the multilateral systems which this paper addresses, the operator manipulates one master robot and some slave robots work toward objects as following the operator's motion. Since the operator can work toward some objects at one time, this system leads to better productivity. In the conventional method, however, the reproduced motion is different from the operator's motion when something inputs an unexpected force into the system. As a result, the conventional system may cause the destruction of the objects. This research aims to improve the performance of slave robots and to reproduce the operator's motion accurately in real time. By using the proposed method, the risk of destroying the objects are decreased. The validity of the proposed method is confirmed through the experiments.