A method can be implemented by a user equipment to update RPLMN information. A PLMN identifier is selected from an available PLMN identifier set that includes PLMN identifiers with RPLMN information, HPLMN information, UPLMN information, and OPLMN information separately. A location update request message that carries the PLMN identifier is sent to a mobile switching center. A TMSI reallocation command is acquired from the mobile switching center according to the location update request message. It is determined whether location update acceptance information that is returned by the mobile switching center according to the location update request message is currently acquired. An operation of updating the PLMN identifier to registered public land mobile network RPLMN information is performed when the location update acceptance information is acquired and the operation of updating the PLMN identifier to RPLMN information is skipped when the location update acceptance information is not acquired.