PURPOSE: To provide the mobile communication system in which no data missing takes place at the time of channel changeover.

CONSTITUTION: A mobile station 20 moves a service area by using a communication channel 61 of a radio base station 51 whose electric field strength is highest in plural radio base stations 51, 52. However, when the mobile station is parted from the radio base station with a highest electric field strength, the electric field strength gets weaker. When an electric field strength monitor section 71 of the mobile station detects it that the electric field strength gets weaker and the electric field strength of a communication channel in use is lower than a threshold level, a mobile communication exchange station 3 of a stationary station 10 selects a communication channel 62 whose electric field strength is strong detected by the electric field strength monitor section at that point of time. A non-voice signal not sent during changeover is stored in 1st and 2nd memories in an inter-working device 4 or the mobile equipment 7 and the stored non-voice signal is sent after the end of changeover of the communication channel.