Precipitation and river discharge are not evenly distributed; and water supply and demand can not match both in time and space. The insufficiency of water resources becomes a very important environmental, political, social and economic issue in present and future Taiwan, especially in southern Taiwan. The present study, which is based on the perspective of geoniorphology and drainage system, firstly, focuses on how geographical subdivision functions in hydrological cycle. Each region is a subdivision of a drainage basin that has its own fluvial and hydrological functions. Then, the possible ways of obtaining water resources from each region and its environmental impacts are discussed. In future study for managing water resources and regional development, the carrying capacity of a drainage basin must be taken into account. The sustainable development of a society should base on inter-regional cooperation and the cyclic utilization of water resources, which has proper negative feedback mechanism.