Abstract: In the era of land spatial consolidation under the background of ecological civilization construction, ecological restoration of territorial space is an important method to improve the ecosystem service function and optimize the spatial structure. According to the method and practice demand of the current ecological restoration of provincial territorial space in the ecological fragile areas of Northwest China, this paper took the county (district) as the basic research unit, combined the supply-demand analysis of ecosystem services with the ecological restoration of land space, used the modified ecosystem service value equivalent to quantify the supply of ecosystem services, and measured the total demand of ecosystem services based on the per capita demand of specified ecosystem services. Finally, this paper explored the method of provincial ecological restoration based on the difference of coupling index between supply and demand of ecosystem services. Gansu Province is an important water conservation area of the Yellow River and the Yangtze River, but it has been trapped with the problem of the mismatch between the supply and demand of ecosystem services for a long time, the human-environment contradiction is increasingly prominent, and the ecological environment problems such as soil erosion and vegetation destruction occur frequently. Based on the physical geographic environment and ecosystem characteristics of Gansu Province, the supply- demand analysis of food supply, carbon sequestration and oxygen release, water conservation and soil conservation services were conducted, and the spatial distribution traits were analyzed. Secondly, based on the supply-demand coupling status of four ecosystem services, the dominant mode of ecosystem services supply-demand coupling in each county (District) were identified. Thirdly, the paper identified the dominant restrictive factors and adjustability of the coupling mode of ecosystem services supply and demand, and then proposed the ecological protection and restoration and its leading direction according to the principle of "protecting ecological source areas and repairing damaged areas". The empirical result of case study in Gansu Province informs us that: 1) in addition to food supply services, the total supply of water conservation services, carbon sequestration and oxygen release services and soil conservation services in counties of Gansu Province is greater than the total demand, but there is a significant spatial mismatch between supply and demand. 2) There are four modes of supply-demand coupling condition in Gansu Province, which are “high supply and high demand”, “low supply and high demand”, “high supply and low demand”, and “low supply and low demand”, and the latter two are the dominant two modes. 3) According to the difference between the supply and demand of regional ecosystem services and the coupling mode of supply and demand, Gansu Province was divided into four ecological restoration regions: Oasis conservation, carbon sequestration, water conservation and soil conservation. Based on the physical geographical environment and regional ecological problems, the 4 regions were further divided into 12 sub regions, and corresponding ecological protection and restoration engineering suggestions were proposed.