This paper proposes a new dynamic load balancing (DLB) method for network traffic. In client-server systems, intense access to a particular server host often causes excessive trafic on a path connected to the server. Although mirror servers are used for load balancing of host performance, this may not be sufficient to balance the load of network traffic. In the DLB method a server has the capability to move to another network, so that flows of packets toward/from the server change and a part ofpackets avoid going through the crowded path. This reduction of the traffic on the congested path achieves load balancing of network traffic. The DLB method is based on Network Transferable Computer (NTC) and Mobile IP. Also a management system is provided. The management system has thefollowing responsibilities. (1) Analyzing packets for the server. (2) Calculating thefluctuation rate of the amount of packets toward the servel: (3)Estimating the future amount of packets. (4) Determining whether the server will move or not and a new location of the server if necessary. The evaluation of this method is underlined by simulations, which will show effective reduction of traffic on the target path.