A base station controller interface of the code division multiple access (CDMA) mobile system is described for interfacing between the base station controller and the CDMA mobile switching center (MSC) of the CDMA mobile system (CMS). The base station controller decreases the load of the system by including, for every base station controller interface, the mobile announcement (MANM) to service the state information of the subscriber of interest for all paging to the mobile subscriber. At the same time, the connection between the base station controller and the base station controller interface of the mobile switching center utilizes the EL 2048 Kbps interfacing technique applying the conventional communication network recommended in the ITU-T. The transmission of the message and the call traffic using the interfacing technique is performed to be linked with the TSB of the base station controller. The control signal for processing the call is accomplished by using the inner communication message protocol which is connected in the EIA-422 interfacing mode to the call control processor of the base station controller. Therefore, the present invention effectively performs the call processing function to the mobile subscriber, the mobility management function, the mobile subscriber announceable function, and the itself operational preservative function. Also, the present invention transmits between the call processing control information and the call traffic. Therefore, the present invention increases the capacity of the subsystem in the conventional full electronic telephone exchanger, and has a effect to easily embody the subsystem in the mobile switching center for more economical connection thereof.