At present, global change is the hot area in geo-science, at the same time, it is also one of the core pans ofgeo-informatics. Global change emphasizes the research on the interaction between the geo-spheres, such as theatmosphere, the biosphere and the hydrological sphere,and on the environmental impacts caused by human beings.Geographic information system(GIS), which has been developing very quickly since 1970s, has been applied to many areas of management of earth resources and environment. But now, GIS is still at its primary stage especially in China, for example only very few of GIS function has been used in the built GIS systems, such assome urban GIS systems built recently in China.From the historical view, that men observe and understand the earth is accelerating in many fields, such as advancement of observing techniques, acquired data amounts and quality etc.. In the space, the earth observingsatellites have been keeping on eyeing our planet and its changes. Much data has been gathered pretty enough formonitoring our environment, and only in this time the each could be studied and understand systematically and onthe global scale.The earth is a very complicated system. In the system much physical process, including gradual changes andsudden changes, exist and sometimes seem hard to predict, and in the unique system, human migration, materialflow, energy flow and information flow interact in its own wad. Observed dsta from space, which is vast andtheme diverse, becomes the base material source to understand global change systematically. But unfortunatelythese data are not fully studied at the present time because of data vastness and method deficiency. As a geospatial information system, GIS should be applied to solve complex problems in geo-science. In global change study, based on observed data of different scales, GIS should be applied tot nature modeling; human-earthrelationship study; pro.jecting and forecasting, and therefore facilitate the global change studies and decisionmakings in the sustainable development planning at present and in the future.