A computer-implemented method for unlocking a terminal, by a first user who belongs to a first preset user group and by a plurality of second users each belonging to a respective second preset user group, the method comprising: receiving an unlocking instruction (101, 201, 301, 401, 501, 601) by a current unlocking user, the unlocking instruction being based on character password information, pattern information; determining whether the current unlocking user belongs to the first preset user group according to the unlocking instruction (102, 202, 302, 402, 502, 602); and starting an information acquisition device if the current unlocking user does not belong to the first preset user group; and acquiring, by the information acquisition device, the information on the current unlocking user; wherein, the information on the current unlocking user comprises biometric recognition information including face image information, voice information or fingerprint information of the current unlocking user; and storing information on the current unlocking user if the current unlocking user does not belong to the first preset user group (303, 203, 603), characterised in that the unlocking method further comprises: determining whether the current unlocking user belongs to a respective second preset user group with permission to use the terminal according to information on the current unlocking user the information comprising biometric recognition information including face image information, voice information or fingerprint information; unlocking a screen and entering a restricted user mode, if the current unlocking user belongs to the second preset user group; and recording an operation of the current unlocking user in the restricted user mode; wherein, in the restricted user mode, a system and/or applications of the terminal only respond to preset operations which comprise one or more of start, inquiry, modification, addition and/or deletion. receiving an unlocking instruction (101, 201, 301, 401, 501, 601) by a current unlocking user, the unlocking instruction being based on character password information, pattern information; determining whether the current unlocking user belongs to the first preset user group according to the unlocking instruction (102, 202, 302, 402, 502, 602); and starting an information acquisition device if the current unlocking user does not belong to the first preset user group; and acquiring, by the information acquisition device, the information on the current unlocking user; wherein, the information on the current unlocking user comprises biometric recognition information including face image information, voice information or fingerprint information of the current unlocking user; and storing information on the current unlocking user if the current unlocking user does not belong to the first preset user group (303, 203, 603), characterised in that the unlocking method further comprises: determining whether the current unlocking user belongs to a respective second preset user group with permission to use the terminal according to information on the current unlocking user the information comprising biometric recognition information including face image information, voice information or fingerprint information; unlocking a screen and entering a restricted user mode, if the current unlocking user belongs to the second preset user group; and recording an operation of the current unlocking user in the restricted user mode; wherein, in the restricted user mode, a system and/or applications of the terminal only respond to preset operations which comprise one or more of start, inquiry, modification, addition and/or deletion. determining whether the current unlocking user belongs to a respective second preset user group with permission to use the terminal according to information on the current unlocking user the information comprising biometric recognition information including face image information, voice information or fingerprint information; unlocking a screen and entering a restricted user mode, if the current unlocking user belongs to the second preset user group; and recording an operation of the current unlocking user in the restricted user mode; wherein, in the restricted user mode, a system and/or applications of the terminal only respond to preset operations which comprise one or more of start, inquiry, modification, addition and/or deletion.