PROBLEM TO BE SOLVED : To disclose personal information of a user only to valid users, and to easily and reliably set a user who browses the information.SOLUTION : User relation information showing a relation between a user and other users is stored in a user relation management server MSV. An access control rule storing conditions for disclosing medical health related information of the user in association with the user relation, is stored in a data provision server PSV. When an information acquisition request is transmitted from a user terminal UT, an inquiry is made from the data provide server PSV to the user relation management server MSV about a relation between the user who made the request and the user in response to the information acquisition request. Whether to permit disclosure of the medical health related information of the user is determined on the basis of the answer result and the access control rule.COPYRIGHT : (C)2011, JPO&INPIT