Apparatus and method for locking communication mode in mobile communication system

The present invention, in the data communication mode, a method of fixing a mobile terminal, the serving cell to the first have performed a connection for a data service in a communication mode, test data service to a process, and the first communication mode on the communication mode fixed in case of performing a connection for the step of setting the signal quality value of a received signal value and the other cells of other cells except the serving cell to a minimum and, after the minimum set-up process, the course of providing a data service, comprising: from the data service provider course, if the signal received value or the signal quality value of the serving cell is greater than the threshold, to include the step of maintaining the first connection to the data service communications mode with the serving cell EDGE cell and when performing data communication where there are GPRS cells overlap, avoid frequent handover between cells EDGE and GPRS and EDGE cell There are further advantages that can provide a data service of a high performance by making use to secure the data communication mode as the communication mode. Mobile communication system. EDGE (Enhanced Data rates for GSM Evolution), GPRS (General Packet Radio Service).