The scientific prediction of supply and demand change of water resources is very important for the regional sustainable development,but most of researches can't consider the demand of ecological water. The paper took the supply and demand system of water resources in Shandong as object, considered the ecological construction and the demand of ecological water ,and used STELLA dynamic software to predict the dynamic change of supply-demand situation of water resources, and utilized support degree to build the warning degree of water resources shortage.Based on th sensitive analysis, the paper proposed countermeasure scheme from four aspects such as economic development, water saving, water project and coordinative development. The results show that the shortage of ecological water in Shandong province is severe. In 2030, the difference of water supply and demand will reach 9 billion m? amonge them one billion will affect local production and human activities. The great attention to economy and water saving scheme go against the sustainable development, while coordinative mode can better balance the use mode of water resources of social economy and ecological environment,and provide scientific base for relaxing the contridiction of water resources supply and demand and optimizing the allocation of water resources,and has important significant for the construction of ecological civilization.