To provide a method by which providers of a variety of services can use personal information by anonymizing the personal information.

An information mediation device is provided with; a first data storage part which stores individual-identification information for identifying an individual and diagnosis result information on the individual; an anonymizing means which excludes prescribed information including a name from the individual-identification information, and stores at least part of either the name-excluded individual-identification information or the diagnosis result information, as the anonymized individual information, in a second data storage part; a means which identifies an individual belonging to each of a plurality of categories stipulated based on information kind in the anonymized individual information stored in the second data storage part by using the information stored in the first data storage part, and stores the identification information of the individual belonging to each of the plurality of categories in a third data storage part; and a method which receives an advertisement mail from a registered providers for each of the plurality of categories included in the third data storage part, and transfers the advertisement mail by using the individual-identification information of an individual belonging to a categories.