A communication control method for a mobile communication system having a plurality of mobile stations, a radio base station, and a radio control station comprises a measurement step, an evaluation step, and a control step. In the measurement step, a plurality of congestion parameters related to factors generating congestion is measured in a mobile communication system. In the evaluation step, the radio control station evaluates a congestion degree corresponding to each of the plurality of congestion parameters. In the control step, a communication setting between the radio base station and at least one of the plurality of mobile stations is controlled in accordance with a control instruction transmitted from the radio control station to the radio base station when at least one of the plurality of congestion degrees is a prescribed level or more.