Reginnal structure is defined here as the spatial combination of the natural, ecological,economic and social structures of a region. It can be divided into some subsystems. Sinceterritorial plannings are usually made in certain regions, the study of regional structure beco-mes an important theoretical work for geographers to do in territorial planning.The study of regional structure should be concentrated in:1. The characters of regional structure. Comprehensive analysis and generalization fromquality to quantiiy.2. The mechanism of regional structural changes. Under the conditions without outerinfluences or with strong outer influences from macro-en-vironment.3. The openness of regional structure. Orderly relations existing among relevant regionswith open unbalanced structure.4. The development stages of regional structure. division in time and space.5. The rationality of regional structure. From five aspects.The study of regional structure can help us to understand the function and differences ofregiona and give scientific basis for defining the utilization dircction of territorial resources,determining the scale and direction of economic development as well as the adjustment of mac-ro-distribution, and planning the industrial structure in accordance with economic performingmechanism a and urban systems.