In an intelligent network system, a service subscriber can remotely execute a procedure, such as a registration or a change of the contents of service, which is performed by an operator in the conventional system, through an external terminal by him or her. The intelligent network system includes a service control point that controls services and provides a database storing data relating to a service subscriber; a service management system, which monitors load on the service control point, stores and manages data relating to the service subscriber; external terminals owned by the service subscriber; and a remote access management system, which is interfaced with the external terminal. The service management system updates and records the data of the updated subscriber's service, which is transmitted through the remote access management system, in the database of the service control point, when the service control point does not over-load.