Abstract: Watershed, ecoregion and landscape frameworks are spatial frameworks used to assess large-scale regional ecological quality. This paper discusses a theoretical basis of reasonable combination of the three frameworks. Watershed has been an integral spatial framework for solving water ecological environmental problems, although research achievements regarding watersheds lack sufficient basis for extrapolation. Ecological regions provide appropriate extrapolation mechanisms, and serve for scaling up and prediction when combined with watershed. Defining a landscape is researcher-dependent. Because districts, watersheds and ecoregions can all be treated as landscapes, landscape is a suitable approach for ecological quality assessment at various scales. We took regional ecological quality assessment in Hai River Basin as a case to show how to integrate the use of watersheds, ecoregions and landscapes. The procedure includes three steps: watershed ecological regionalization, landscape assessment of pilot districts in ecoregions, and scaling up. An index of landscape assessment was built and the data were translated from RS imaging. Finally, strategic countermeasures for ecoregion conservation were put forward according to the ecological process of the whole basin. These included soil and water conservation in the mountain area, water saving and rivers and groundwater system conservation in the plain, and wetland conservation and freshwater discharge increase in the coastal zone.