A mobile phone, comprising a mobile phone body and a mobile phone accessory, wherein the mobile phone accessory comprises a mobile phone card configured to communicate with an external communication device, a storage module configured to store user data and a second communication module configured to establish wireless communication with the mobile phone body, and a mobile phone body verification module configured to verify user data or operation instruction sent from the mobile phone body and judge whether the mobile phone body is valid according to the verification result; wherein the mobile phone body verification module is further configured to verify user data or operation instruction sent from the mobile phone body and judge whether the mobile phone body is valid according to the verification result by following steps: verifying whether the user data or operation instruction received is from the mobile phone body corresponding to identification information stored in the mobile phone accessory; if so, determining that the mobile phone body is valid, otherwise, determining that the mobile phone body is invalid; and the mobile phone body comprises: a first communication module configured to perform data interaction with the second communication module and establish wireless communication between the mobile phone body and the mobile phone accessory; a mobile phone card information reading module configured to read information of the mobile phone card in the mobile phone accessory; a basic communication module configured to communicate with an external communication device according to the information of the mobile phone card; and a data transmission control module configured to send an operation instruction to the storage module, to store the user data stored in the storage module to a local memory or update user data in the local memory to the storage module; wherein the mobile phone body further comprises: a verification module, configured to verify whether the identification information in the mobile phone accessory is consistent with the identification information locally stored in the mobile phone body; a security control module, configured to clear the user data stored in the local memory if the identification information in the mobile phone accessory is inconsistent with the identification information locally stored in the mobile phone body. a first communication module configured to perform data interaction with the second communication module and establish wireless communication between the mobile phone body and the mobile phone accessory; a mobile phone card information reading module configured to read information of the mobile phone card in the mobile phone accessory; a basic communication module configured to communicate with an external communication device according to the information of the mobile phone card; and a data transmission control module configured to send an operation instruction to the storage module, to store the user data stored in the storage module to a local memory or update user data in the local memory to the storage module; wherein the mobile phone body further comprises: a verification module, configured to verify whether the identification information in the mobile phone accessory is consistent with the identification information locally stored in the mobile phone body; a security control module, configured to clear the user data stored in the local memory if the identification information in the mobile phone accessory is inconsistent with the identification information locally stored in the mobile phone body.