In the context of global warming and the rapid development of urban agglomerations leading to the destruction of landscape patterns and the impairment of ecosystem service functions, it is important to study the relationship between ecosystem service functions and landscape patterns in urban agglomerations. Based on the above background and previous studies, this paper selects the most representative urban cluster in China's economic and social development, the Beijing-Tianjin-Hebei urban agglomeration, and studies its ecological spatial carbon sequestration service function and its relationship with the landscape pattern from the perspective of land use through remote sensing interpretation, ArcGIS 10.6 mapping analysis and SPSS software correlation analysis, and proposes relevant discussions. The results show that:1) the cultivated land, forest land and grassland are carbon sink lands in the ecological space of the Beijing-Tianjin-Hebei urban agglomeration. The land area ranking during 2000-2018 was cultivated land > forest land > grassland, while the land area reduction ranking was forest land > cultivated land > grassland. (2) The annual carbon sequestration of the three types of land in ecological space during 2000-2018 was ranked as follows:arable land > forest land > grassland, and the increase in annual carbon sequestration of land was ranked as arable land > forest land > grassland. In terms of average carbon sequestration per unit, all four time points showed that forest land > cropland > grassland. (3) The correlation between the amount of carbon sequestered by different ecological sites and different landscape indices was different. There was no significant correlation between the annual total carbon sequestration of cropland and its landscape indices; the annual total carbon sequestration of forest land had a significantly positive correlation at 0.01 level with the largest patch index (LPI), landscape shape index (LSI) and percent of landscape (PLAND); the annual total carbon sequestration of grassland had a significantly positive correlation at 0.05 level with the patch density (PD) and PLAND, and a significantly positive correlation at 0.05 level with the LSI. The total annual carbon sequestration in grassland was significantly and positively correlated with patch density and percent of landscape at 0.05 level, and with LSI at 0.01 level; the total carbon sequestration in ecological space was significantly and positively correlated with LSI at 0.01 level. Finally, a discussion of the relevant causes is presented. The study also proposes a strategy for optimizing ecological land use in ecological space of the Beijing-Tianjin-Hebei from the perspective of land use based on the relationship between carbon sequestration service function and landscape pattern.