Considering the relationship between the water demand, available water resources and the form of the regional ecosystem, we establish the model on the basis of urban ecosystem. For water demand, we take the urban living water demand, industrial water demand, natural environment water demand and agricultural water demand into consideration. For available water resources, surface water, groundwater and other water resources are taken into consideration. The water scarcity situation in this region can be measured by the index of balance of water supply and demand and the water scarcity rate. The city of Qingdao is chosen as the research object, which is in seriously short of water. In the process of analyzing the supply and demand of water resources in Qingdao, for different quantities, regression analysis is made with various ways. We find that if no measures are taken, the situation of water scarcity will be intensified in the coming 15 years in Qingdao and the index of balance of water supply and demand will be 1.376.
