Based on the clarification of the character of scale, the spatial and temporal scale of river ecosystem restoration is discussed in detail. The temporal scale includes short, middle, long and bally long scale, the longer is the time required to make river ecosystem get stabilization state, the larger is the selected temporal scale. In restoration practice, river ecosystem restoration commonly focuses on short, middle and long scale. The spatial scale consists of region, watershed, river corridor and river section scale. The focus in region scale is the optimization of socio-economic disturbance sources and the dissipation of disturbance intensity, the integrity of watershed, cumulative impacts, landscape pattern and process, land use and other aspects should be emphasized in watershed scale, the longitudinal, transverse and vertical link should be given special consideration in river corridor scale, and river section is the implementing unit for detailed restoration project and engineering.