A designed network control system of multi mobile robot is presented. It is based on wireless distribution system. One or more mobile robot and some other devices are connected via wireless network to form a network control system. More than one wireless node is provided in order to realize distribution wireless network and extend the coverage range. The hierarchy control structure is used in the robot control system. It is optimized by the features of the network control system especially in time delay. By testing the time delay in different network environment, the performance of the whole control system can be proved.