Abstract: [Objective] The level of grassland carrying capacity affects the sustainability of grassland utilization and the security of grassland ecosystems. As an important ecological barrier in the north, an in-depth study of the carrying capacity of grassland resources in Xilingol League can provide a scientific basis for the regional ecological security and sustainable use of grassland and the construction of ecological civilization. [Methods] This study analyzed and evaluated the status of grassland resource carrying capacity, ecological deficit (ED)/ remainder (ER) and ecological pressure index of Xilingol League of Inner Mongolia based on three-dimensional ecological footprint model, by using land use and other relevant data in 2013, 2015, 2018 and 2020. [Results] (1) The ecological footprint continued to be higher than the ecological carrying capacity, and the total ecological footprint and total ecological carrying capacity showed a trend of first increasing and then decreasing, decreasing by 2.76% and 7.35% respectively within 7 years. The change rates of per capita ecological footprint and per capita carrying capacity in 7 years were -9.62% and -13.19%, respectively. The ecological footprint decreased from east to west, and the ecological carrying capacity in the east and north was higher than that in the west and south . (2) The ecological footprint depth first increased and then decreased, with an overall increase of 4.95%, which was greater than 1. The grassland ecosystem remained in an ecological deficit for many years, indicating the grassland was unsustainable and unhealthy. (3) The results of ecological profit and loss and ecological pressure index reflecting the ecological security of grassland showed that ER/ED was less than 0 and the ecological pressure index was greater than 1 in the four periods of the study area. The ecological carrying state of grassland was continuously overloaded for many years, and the ecological security and stability continued to decrease. [Conclusion] The arid and semi-arid geographic location of Xilingol League and its resource endowment, superimposed on high-intensity human economic and social activities, have led to a reduction in the ecological carrying capacity of the grasslands of the League, and the ecology is in an extremely insecure state.