Abstract: The paper reports on the technical problems of the detailed control planning of the central zone of Hengshui city with the help of comprehensive techniques such as computer scaning techniques、GIS、CAD and the original planning methods. In this paper, the authors put forward the planning characteristics to some medium and small cities, offer solutions to some general problems. Meanwhile, according to the characteristic of spatial information which is necessary for urban planning, the authors advance the new concept of "cooperate spatial unit", which will be helpful to operate the UPMS (urban planning & management system) and enrich the theory of GIS.