In the context of urbanization, contradictions between human beings and the natural environment have shown the characteristics of multi-scale and hierarchy. While the traditional construction of ecological network paid little attention on the relationship between ecological elements at different scales which could not be implemented from the region to the central city. So it was difficult to form a systematic solution to these problems. Based on a comprehensive review of ecological network construction methods at different scales, taking Changsha City as an example, we identified ecological sources through Morphological Spatial Pattern Analysis (MSPA), landscape connectivity theory and the evaluation of the importance of ecological patches. After determining the multi-level ecological resistance surfaces, we used the least cost path method (LCP), circuit theory, hierarchical transmission theory, scale nesting and other methods to study the coordinated construction and hierarchical optimization of ecological networks in the urban area, metropolitan area and central urban area. Finally, based on the characteristics of ecological networks at different scales, the research results were applied to the multi-level land spatial planning system. The results showed that:(1) the urban ecological network and metropolitan ecological network had good hierarchical nesting characteristics. The number of ecological overlapping sources and corridors on the two scales were 14 and 15, respectively, which were mainly connected with the peripheral ecological green circles through the Xiangjiang River, Liuyang River and Laodao River in the central urban area, forming the spatial pattern of "outer ring and inner wedge". (2) The core protection area of important corridors in the urban area, potential corridors in the urban area, ecological overlapping corridors, important corridors in the metropolitan area, and potential corridors in the metropolitan area was 501.14 km², from which we extracted ecological pinch points and ecological barriers for further ecological protection and restoration. (3) The length of ecological greenway in the central urban area with important ecological connectivity functions was 441.2 km. And the number of ecological restoration units was 56, which was divided into 5 levels combined with the ecological resistance value for the targeted restoration. (4) Based on the connection and nesting of ecological sources, corridors and node patches at different scales, we finally constructed the overall ecological security pattern of the urban area-the urban ecological spatial development pattern of the metropolitan area-the ecological restoration unit of the central urban area based on the urban greenways, which corresponded to the land spatial planning system at different levels. The research results could provide a scientific reference for the cross-scale ecosystem restoration and ecological security pattern construction centered on large cities.