Land ecological security is the core of sustainable use of land resources, and land use changes caused by human activities change the structure and function of ecosystems, which have a serious impact on the regional ecological security system. In order to explore the changes in ecological security in Chongqing in recent years and in 2030, Chongqing was taken as the research object and PLUS (patch-level land use simulation) model was employed to simulate land use changes under the scenarios of natural development, ecological priority and development priority in 2030. Based on the ecological perspective, an ecological security evaluation index system was constructed, and the mutation model was combined to quantitatively evaluate the level of land ecological security. The results show that the spatial distribution of land use types in Chongqing is quite different, the cultivated land area decreased by 3 995.14 km², and the construction land area increased by 1 147.36 km², realizing rapid urban development. At the same time, 64.53%, 67.31% and 55.97% were relatively safe or above under the three scenarios. The spatial pattern of ecological security in Chongqing is opposite to the spatial pattern of population density and GDP, and consistent with the spatial pattern of natural data such as vegetation cover and slope. Through the ecological assessment of land use changes in previous years and under different scenarios, it provides a basis for high-quality coordinated development of ecology and economy.