A security management system is provided. The security management system includes a storage unit and at least one processor. The storage unit stores a restricting table which records relationships between positional information of a mobile device and functions of the mobile device. The at least one processor includes an information module, a restricting module and a disabling module. The information module provides positional information of the mobile device. The restricting module generates a restricting instruction according to the provided positional information of the mobile device and the restricting table. The disabling module disables the corresponding functions of the mobile device according to the generated restricting instruction.