Ordos City was chosen as a typical study area, landscape pattern data and meteorological and hydrological data from 2000, 2005, 2010, 2015 and 2018 were taken as the study material. Based on complex network theory, landscape ecology and GIS spatial analysis technology, the spatial and temporal landscape pattern evolution of Ordos and the water sources depth in various subwatersheds were quantitatively analyzed. The data of landscape pattern evolution and ecological hydrology were coupled with the landscape ecological network constructed according to the multiple factors that determined the landscape characteristics, which provided reference for the landscape pattern optimization and ecological environment construction in the study area. The results showed that arable land in Ordos City was decreasing, woodland, grassland, waters and building land was increased to some extent over the study period. Landscape evolution occurred mainly between arable land, woodland and waters, with the most dramatic landscape evolution occurring in woodland and waters, and it was relatively stable in arable land, grassland and building land. The overall water retention capacity of Ordos region was low, with the eastern region relatively stronger than the western region. Over time, the high values were gradually shifted southward. There were 342 ecological nodes and 402 ecological corridors in the Ordos landscape ecological network, with 119 corridors added based on the strategy of adding edges with the lowest priority. The optimized network connectivity and connectivity robustness were significantly improved, and the ecological fluidity in the network was smooth.