Abstract:The Heihe River is the second largest inland river in northwest China, where the national integrated management project was executed in 2001. Based on the research results and periodicity understanding on the hydrologic cycle, process of nature-society system, and eco-environmental changes of the Heihe River Basin, the scientific assessment on the ecological and environmental effects is carried out. Generally, the water resources of the river are influenced by the Westerlies, and the alp and sub-alp are the main runoff producing area. The last decade and last century are the high flow periods of the instrumental records and on the millennium scale in the Heihe River. This above normal water resources level provided a powerful guarantee for the water division and the integrated management of watershed. Nevertheless, the pressure from increasing water demand of the local socioeconomic system is the main cause of the conflict between the water use by the middle and the lower reaches of Heihe River, and between the economic development and ecological water utilization. Under the effective control of water utilization volume in the middle reaches, the water utilization structure of the socioeconomic system has changed significantly. Because of the limited water resources and the continued increasing farmland area, the grounder water level and volume reserve presents locally decreased tendency in the middle reaches, and it will face serious overloading of water resources in the future lower runoff period. The quantity of water flowed into the lower reaches closes to the request of the water division, the deteriorated tendency of ecology and water environment got restrained, but it has not recovered and has stronger spatial heterogeneity. More elaborated adjustment measures and spacetime administration of the limited water resources are needed, because the increasing farmland from the reclaimed riparian forestland will bring more pressure between the farmland and ecologic water utilization. In the possible lower runoff future, the water resources management of Heihe River Basin will face greater challenge under the sustainable development aim of society-economy-ecology in the whole watershed.