And a method of operating a mobile communication device of the method

The present invention discloses a mobile communication method, comprising: a terminal using the procedure master account information of the home network; Step module transmission request command subsidiary number to the service side of the support module control; server support module receives the request for subsidiary account a subsidiary account assignment command, and the process returns to step subsidiary account information to the control module of the terminal; a terminal using the account information registered in step affiliated networks. Further, the present invention also discloses a server and a terminal run of the process. The present invention provides a mobile communication method and apparatus for operating the method can effectively reduce roaming charges, and transformation of a low cost network, the user uses a low cost.