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Baotou is a typical semi-arid city in Northwest China. The hierarchical ecological network model was used to construct the hierarchical ecological network of Baotou City. Based on the complex network theory, the static characteristic index and spatial robustness index were calculated, and the topological structure of the complex hierarchical ecological network was analyzed. The results showed that the first, second and third ecological sources and the first, second and third ecological corridors were extracted by using the hierarchical ecological network model, and the important ecological nodes were identified. The number of ecological sources in the first, second and third layers was 8, 31 and 123, the number of ecological corridors was 8, 35 and 151, and the number of important ecological nodes was 7, 28 and 47, respectively. The first layer of ecological network had the lowest connectivity and two cores. Its structure was simple but its importance was the highest. The stability of the first layer of ecological network affected the stability of the whole region’s hierarchical ecological network. The second layer of ecological network can increase the small-scale ecological stability by increasing the ecological nodes with low connectivity, and had no obvious effect on the stability improvement of the largescale ecological network. The third layer had four cores, and the highest connectivity structure of the ecological network was complex. Malicious attacks were more destructive than random attacks. The number of source nodes in the second layer and the third layer ecological network was large, but the proportion of lowlevel source sites was high, and the antiattack ability and recovery ability of the network were not obviously enhanced.