The present invention relates to a radio communication trunking system control method. According to the control method, a channel (f1), which is normally used as a control channel, is used as a telephone communication channel when a plurality of channels (f2-fn), used as telephone communication channels, are being used. For example, the channel (fn) has been adapted to be able to operate not only as a telephone communication channel but also as a control channel. When the telephone communication using the channel (fn) is completed, the channel (fn) is established as a control channel in place of the channel (f1). In this way, the currents consumed by wireless units accommodated in a trunking system can be reduced, and the time period for which the trunk operation is inoperative can be significantly reduced.