Exploring ecological land stability pattern is of great importance for regional ecological planning and management in the context of the dynamic development of urbanization. Based on the data on ecological land use in the Beijing-Tianjin-Hebei region in 2000, 2010, and 2020, we extracted the stable ecological land in 2000-2010 and 2010-2020. We used the ecological land stability index to describe the spatial and temporal dynamics of ecological land stability. At the same time, we analyzed the spatial pattern of the ecological land stability index. Finally, we utilized the geographical detection model to explore the influencing mechanism and regional differences in the ecological land stability. The results showed that:(1) the area of stable ecological land decreased in the two periods, which were more in Inner Mongolia Grassland Ecological Zone and Yan-Taihang Mountain Forest Ecological Zone. (2) Ecological land stability indexes were 90.85% and 83.86% in two periods, which were higher in the northwest and lower in the southeast. The area of the grade of stability, which is named extremely low and extremely high, was the most important from 2000 to 2010. The area of the class of stability, which is called extremely low, high, and extremely high, was similar from 2010 to 2020. The ecological land stability index had cold/hot spots. The area of the hot spots was more in Yan-Taihang Mountain Forest Ecological Zone and Inner Mongolia Grassland Ecological Zone. The area of the cold spots was more in Beingjing-Tianjin-Tangshan City Ecological Zone and North China Plain Ecological Zone. (3) In the study area, the explanation intensity of the elevation, the slope, the landform, and the soil factors was higher. In the plain area, the temperature had the highest explanatory power. The geographical and social-economic factors also had superior explanatory power; in the mountainous area, the influence of GDP, population density, settlement density, and road density was more pronounced.