PURPOSE: To obtain an economical system constitution as an incoming transferring service subscriber is increased by executing the preparing for corresponding to the line linking frame storing position information of the service subscriber and a transferring destination telephone number.

CONSTITUTION: After a service starting condition is set, when incoming is executed to a subscriber, a connecting marker (CM) is started from an incoming trunk ICT, the connecting marker CM starts a number group NG by an SUB telephone number. At the number group NG, in order to set incoming transferring service information TTS can be returned together with SUB storing position information to the connecting marker CM only for an incoming transferring subscriber beforehand, at the connecting marker CM, a control unit CONT is started by TFS information and the SUS storing position information is sent. While the service is started, the incoming terminal storing position information of an incoming transferring equipment TFE set beforehand and service starting information are returned to the connecting marker CM and the connecting marker CM is connected between the incoming trunk ICT and the incoming terminal of the incoming transferring equipment TFE.