The invention relates to the field of communication, and particularly relates to a network management system and a network management method. With the system and the method, network element devices can be grouped according to time needed for the network element devices to transmit data, moreover, execution time of a thread allocated for each group of the network element devices is corresponding to the time needed for the group of network element devices to transmit data, thus, time of each thread is used fully, thread deadlock is avoided, and data transmission efficiency is improved.