This paper proposes a design method of multilateral systems including system connection. To consider system connection, the proposal uses a reachability matrix. A multilateral system enables us to transmit haptic information between many human operators. If the multilateral systems consists of many master system and one slave system, many operator can share the haptic information of an environment in the slave system. However, a conventional multilateral system is difficult to realize independent operation of master system. The cause is that a control object is realization of position synchronization in all subsystem. Here, subsystem stands for master and slave system of multilateral systems. Therefore, control design has to introduce another view point for independent operation of multilateral systems. The proposed method pays attention to system connection. Concretely, arrival information between sub-systems is derived by a reachability matrix, to consider system connection in control design. The arrival information is defined as information transmitted between subsystems. In considering the arrival information, control design considering system connection is possibility. By using the proposal, the multilateral system enables many human to operate independently. The validity of the proposed method is confirmed by the experiments.