A mobile communication system is constructed including a plurality of cluster heads, cluster members, a topology management device, and a location management device. Each cluster head exchanges routing information with only each cluster member in a cluster to which the terminal itself (host terminal) belongs, and with only a cluster head in another cluster adjacent to the cluster to which the host terminal belongs. Each cluster member exchanges routing information with only a cluster head in a cluster to which the host terminal belongs. The topology management device and location management device receive the routing information from each cluster head only.