Abstract: Starting from the thinking about the representations of geo-spatial data in computer networks,this paper points out the challenge of grid computing environment to geo-spatial information science and technology.After the review and summation of the achieved progress and existing problems of geo-spatial information systems,the authors propose a new representation method for spatial data and spatial information——the spatial information multi-grid(SIMG),which can not only easily run at grid computing environment,but also properly consider the difference of natural and social characteristics in earth space as well as the different level of economical development in different areas.The system structure,data representation,data storage and data access in SIMG are described with emphasis on key techniques.The data conversion and transferring between SIMG and conventional spatial databases are also discussed.