A person authentication system capable of performing personal authentication by comparing templates that is personal identification data with sampling information input by a user is disclosed. For example, a service provider (SP) or a user device (UD) acquires the templates from a person identification certificate (IDC) generated by a personal identification certificate authority that is a third party to thereby perform personal authentication. The IDC stores data, such as a certificate identifier and a user identifier, in accordance with a format, and also stores encrypted templates in a manner that the data can be decrypted by an entity that performs authentication. This arrangement achieves efficient template retrieval and a personal authentication process, as well as effective prevention of the templates from being leaking out.