The technology of management for spatial data in RDBMS is currently one of the research focus. In GIS integrated environment

the embedded database engine of spatial database and attribute database is encapsulated entirely by GIS platform and its efficiency is quite high. But it is difficult for spatial database engine (SDE) to operate mass database and manage application system of GIS with client (browser)/server structure. Although the functions of commercial enterprise RDBMS are very perfect

it do not still meet special demands of GIS

that is

it must be able to process spatial data (maps) in database. The spatial database engine (SDE) makes the RDBMS to be able to manage the spatial data and build relationships with attribute data. In this paper

a data structure model of spatial data engine (SDE) is presented. The paper analyses the system structure of the data model

the data organization and the expression of spatial graphical features. According to the given data structure model

we realize the operation of storage

topologic arithmetic and topologic analysis for spatial graphical data in RDBMS based on SQL Server. The application in land registration system shows that Spatial Database Guide (SDG) based on given data structure model runs reliably and well which cab be used widely in development of GIS.