User information relating method, system and server

The invention relates to a user information relating method. The method comprises the steps that a user information relating server receives a relating request sent by a first terminal or a first client-side; identification is carried out through an agent approach or relating confirmation is carried out through transmission, and if the request passes the identification or the relating confirmation, relating operation is carried out on user identifier information corresponding to the first terminal or the first client-side and user identifier information corresponding to a second terminal or a second client-side according to a preset relating strategy; during the relating operation process, a relating relation tuple is retained and updating is carried out to user identifier information stored by the first terminal or the client-side according to the relating relation tuple. The invention further relates to the user information relating server and a user information relating system. The user information relating method, the user information relating server and the user information relating system relate user information in various terminals or various client-sides, provide uniform individual service for users across the terminals or the client-sides, lower the threshold of experiencing system individual service for the users, and provide later management flexibility, initiative and convenience of user information for the users.