A method for switching subscriber modes through identifying an International Mobile Subscriber Identification Number, IMSI, wherein the method comprises: - when the cell phone is turned on, reading, by the cell phone, a first IMSI of a first SIM card inserted into the cell phone (S100; S1-S2); - determining, by the cell phone, if the read first IMSI corresponds to a second IMSI pre-stored in the cell phone at the previous shutdown of the cell phone (S200; S3); - if the read first IMSI corresponds to the second IMSI, entering, by the cell phone, a subscriber mode corresponding to the second IMSI (S200; S6); - if the read first IMSI does not correspond to the second IMSI, then the first IMSI is matched, by the cell phone, with an IMSI list pre-stored in the cell phone (S300; S4); and - when the matching is successful, entering, by the cell phone, the subscriber mode corresponding to the IMSI in the IMSI list that is successfully matched (S300; S6), wherein the IMSI list pre-stored in the cell phone has been created prior to the step when the cell phone is turned on by: - setting up an IMSI list in the cell phone, receiving IMSI input by a subscriber and storing it into the IMSI list, receiving the subscriber mode configuration set by the subscriber for the IMSI, storing the subscriber mode in the IMSI list and correlating to the corresponding IMSI; the method characterized in that: the second IMSI has been pre-stored in the cell phone by: - when the cell phone is shut down at the previous time, recording, by the cell phone during shut down, the IMSI of the SIM card being inserted into the cell phone and the information of its corresponding subscriber mode, and storing this IMSI as the second IMSI and the information of its corresponding subscriber mode in a cell phone memory. - when the cell phone is turned on, reading, by the cell phone, a first IMSI of a first SIM card inserted into the cell phone (S100; S1-S2); - determining, by the cell phone, if the read first IMSI corresponds to a second IMSI pre-stored in the cell phone at the previous shutdown of the cell phone (S200; S3); - if the read first IMSI corresponds to the second IMSI, entering, by the cell phone, a subscriber mode corresponding to the second IMSI (S200; S6); - if the read first IMSI does not correspond to the second IMSI, then the first IMSI is matched, by the cell phone, with an IMSI list pre-stored in the cell phone (S300; S4); and - when the matching is successful, entering, by the cell phone, the subscriber mode corresponding to the IMSI in the IMSI list that is successfully matched (S300; S6), - setting up an IMSI list in the cell phone, receiving IMSI input by a subscriber and storing it into the IMSI list, receiving the subscriber mode configuration set by the subscriber for the IMSI, storing the subscriber mode in the IMSI list and correlating to the corresponding IMSI; the method characterized in that: the second IMSI has been pre-stored in the cell phone by: - when the cell phone is shut down at the previous time, recording, by the cell phone during shut down, the IMSI of the SIM card being inserted into the cell phone and the information of its corresponding subscriber mode, and storing this IMSI as the second IMSI and the information of its corresponding subscriber mode in a cell phone memory. - when the cell phone is shut down at the previous time, recording, by the cell phone during shut down, the IMSI of the SIM card being inserted into the cell phone and the information of its corresponding subscriber mode, and storing this IMSI as the second IMSI and the information of its corresponding subscriber mode in a cell phone memory.