Network locking method and device for mobile terminal

A network locking method and device for a mobile terminal are provided in the present document, wherein network locking information and verification signals of a mobile terminal and a subscriber identify module (SIM) card are respectively stored in both parties in advance; after the mobile terminal is powered on, the mobile terminal and the SIM card verify each other through the verification signals; if the both parties pass through the verification performed by the other party, the mobile terminal compares the stored network locking information with the network locking information in the SIM card; if the comparison result indicates consistency, the mobile terminal enters into a normal standby state. Compared with the present art, even if the Mobile Country Code (MCC) and the Mobile Network Code (MNC) in the mobile terminal are cracked, and a non-customized SIM card is inserted, because the non-customized SIM card can not perform verification operations with the mobile terminal, the non-customized SIM card still can not be identified and used, thereby improving the security of the present network locking mechanism. Furthermore, In addition, in the present document, a network locking flag is also set in the network locking information, which not only improves the security of the network locking information comparison process, but also is convenient for the unlocking operation by the related legitimate personnel such as operators.