Web database security is a very important issue in E-commerce. This paper presents a new Web database security model. It utilizes the Host Identity Protocol (HIP), which is being defined by the IETF, and a proposed User Identity exchange, to achieve authentication of Host Identity and User Identity, and combines it with the database system itself and encryption to guarantee Web database security and confidentiality of the data. For these purposes, we define a new concept of the User Identity namespace for the user, and using it to realize the binding-authentication of the Host Identity and User Identity of the client, and build a relationship between the host and the user. In the new Model, we set up a high strength shell of security for the database.