A guardian service provision system which provides a guardian service for monitoring a guarding target (Ch) through an information terminal possessed by the guarding target (Ch), the guardian service provision system comprising: the information terminal, comprising an application execution unit configured to execute an application on an operating system, OS, of the information terminal; a positional information acquisition unit configured to measure a current position of the information terminal as a function of the OS; an OS side notification unit configured to notify the application, as a function of the OS, when the current position of the information terminal moves out of a monitoring area; a notification acquisition unit configured to acquire, as a function of the application, a notification from the OS side notification unit; and the guardian service provision system further comprising a service providing unit implemented in a server device which is installed on a communication network; the guardian service provision system further comprising a management terminal which is another information terminal than the information terminal and is configured to be connected to the information terminal through a communication network, the management terminal comprising: a monitoring area setting unit configured to set the monitoring area to the positional information acquisition unit; a remote operation unit configured to perform operation of the application through an application execution unit of the information terminal, and wherein a way of deleting the positional information in the information terminal is set up remotely in the information terminal. the information terminal, comprising an application execution unit configured to execute an application on an operating system, OS, of the information terminal; a positional information acquisition unit configured to measure a current position of the information terminal as a function of the OS; an OS side notification unit configured to notify the application, as a function of the OS, when the current position of the information terminal moves out of a monitoring area; a notification acquisition unit configured to acquire, as a function of the application, a notification from the OS side notification unit; and an application execution unit configured to execute an application on an operating system, OS, of the information terminal; a positional information acquisition unit configured to measure a current position of the information terminal as a function of the OS; an OS side notification unit configured to notify the application, as a function of the OS, when the current position of the information terminal moves out of a monitoring area; a notification acquisition unit configured to acquire, as a function of the application, a notification from the OS side notification unit; and the guardian service provision system further comprising a service providing unit implemented in a server device which is installed on a communication network; the guardian service provision system further comprising a management terminal which is another information terminal than the information terminal and is configured to be connected to the information terminal through a communication network, the management terminal comprising: a monitoring area setting unit configured to set the monitoring area to the positional information acquisition unit; a remote operation unit configured to perform operation of the application through an application execution unit of the information terminal, and a monitoring area setting unit configured to set the monitoring area to the positional information acquisition unit; a remote operation unit configured to perform operation of the application through an application execution unit of the information terminal, and wherein a way of deleting the positional information in the information terminal is set up remotely in the information terminal.