[Objective] As a unique mountainous ecological hot spot in Inner Mongolia Autonomous Region, the response relationship of land circulation and intensity to ecosystem service function was studied to provide theoretical basis for scientific allocation of land use pattern and ecological sustainable development in Daxinganling. [Methods] Based on five remote sensing images captured from 1990 to 2022, this study comprehensively applied the InVEST-CASA and four-quadrangle models to assess changes in five typical ecological service functions (habitat quality, carbon storage, water conservation, soil conservation, and the net primary productivity of vegetation) at the county scale. The correlation between the temporal and spatial evolution of land use intensity and ecosystem service function was studied. [Results] ① From 1990 to 2022, the land use pattern of the study area was stable, and farmland, grassland, and woodland (natural forest and plantation forest) were the main land types in the Daxinganling Mountains of Inner Mongolia. ② Ecosystem service function showed a trend of slower degradation in the north and lower degradation in the south, the habitat quality and soil conservation decreased annually, the water production and the net primary productivity of vegetation declined in a fluctuating manner, and the growth rate of carbon storage slowed down. ③ Owing to the change in the land use pattern and the increase in land use intensity, there was a negative correlation between the comprehensive value of ecosystem service function and land use intensity, and counties affected by this change were mainly distributed in the southeastern region of the study area. [Conclusion] There was evident spatial and temporal heterogeneity in ecosystem services in the Greater Khingan Mountains of Inner Mongolia, and rational optimization of land use patterns can effectively improve ecosystem services in this area.