Abstract: In a call distribution control method for terminating an incoming call from a trunk or another extension at a pilot extension in a private branch exchange and routing the incoming call from the pilot extension to an idle agent in an agent group, a routing table corresponding to the pilot extension is provided for designating one or plural agent groups to which the incoming call is to be routed. Priorities are assigned to agents constituting the agent groups, and an agent group to which the incoming call is to be routed is decided, based upon the routing table when the incoming call is terminated at the pilot extension. The incoming call is routed to an idle agent, in the order of priority thereof, in the agent group to which the incoming call has been routed. Further, a prescribed agent is allocated to a plurality of agent groups upon assigning a priority to this agent.