To provide a method and system for telephone number directory guide in which a user can securely inform a desired person of his or her telephone number without spending much time and efforts.

When this system accepts a request from an inquirer for the telephone number directory guide regarding a registered person, it firstly judges whether the telephone number of the registered person in question is listed on a database 210 or not. If it is listed, the system also judges, based on the disclosure conditions 218 registered on the database 210, whether the massage from the inquirer should be notified to the registered person before informing the inquirer of the telephone number. If the notification needs to be made, the system prompts the inquirer to type the message, and then sends the message to the registered person.