Abstract: Ecological land plays an important role in maintaining regional ecological balance and ensuring regional ecological security. Taking Xingyun Lake Basin in Yunnan  Province as the study area and using AHP and GIS technology, from the soil and water conservation, geological disaster avoidance and protection, biodiversity protection and water resources security, this paper constructs the important ecological land identification index and its identification method, and identifies the spatial distribution of  important ecological land . Results show that （1）WSM is more suitable for identifying important ecological land in Plateau Lake Basin；（2）The area of important ecological  land belonging to core type，auxiliary type，transitional type and non important ecological land was 7598 km2，10505 km2，8947 km2 and 6511 km2，respectively, and  accounting for 2264%，3130%，2666% and 1940% of the total ecological land.The results can reflect the important ecological land to maintain ecological security of the basin. Xingyun Lake Basin as a typical Plateau Lake Basin, provides scientific direction for the ecological protection of the plateau lake, achieves a win-win between economic  development and ecological protection, and promotes the sustainable development of the basin.
Key words：Important ecological land;GIS;Weighted stacking; Plateau lake;Xingyun lake basin