It is a period of explosibility information. Especially for spatial information science, information can be acquired through many routes, such as man-made planet, aeroplane, laser, digital photogrammetry and so on. Spatial data sources are usually distributed and heterogeneous. In order to share and interoperate spatial data, federated database is the best resolution. In this paper, the concepts of federated database and interoperability are introduced. Three heterogeneous kinds of spatial data, vector, image and DEM are used to create integrated database. A data model of federated spatial databases is given.