A location registration method, apparatus, and system protects against unnecessary power waste by a mobile terminal. The location registration method includes receiving a location registration accept message from a connected network in response to a location registration request message; comparing a connected network information contained in the location registration accept message with a home network information stored in the mobile terminal; and determining, if the connected network information is different from the home network information, whether or not to perform a home network search based on a home network presence indicator contained in location registration accept message. Battery usage of the mobile terminal can be decreased, as well as the energy spent for recharging the battery of the mobile terminal.