To precisely control traffic corresponding to communication situations at every terminal by restricting communication by means of adding the number of packet processings and communication time bands for respective terminals on a congestion control system at the high load traffic of a packet exchange.

A packet exchange controlling communication restriction when congestion occurs is provided with a subscriber traffic monitoring part 2 measuring the processing number of packets within prescribed time for respective subscribers, a communication restriction control part 4 comparing the measured processing number of the packets for the respective subscribers with a packet processing number upper limit value for the respective subscribers, which are previously set, judging the propriety of packet in-flow restriction for the subscriber and giving the notice of in-flow restriction or restriction release of the packets and an exchange processing part 5 executing the processing or the in-flow restoration or restriction release of the packet from the subscriber in accordance with the notice. Thus, a traffic controller is constituted.