Abstract: The spatial pattern of carbon sinks in estuarine delta regions can greatly contribute to the territorial spatial planning under carbon neutrality goals. This study aims to explore the carbon sink pattern and spatial optimization zoning in the Yellow River Delta of China. Spatiotemporal evolution of regional carbon storage was also examined to explore the spatial strategies for the high carbon sink capacity. Multi-temporal data of land use was interpreted from Landsat images. Land use dynamics were then characterized between 1990 and 2020. Carbon storage was finally estimated using the carbon storage module of the Integrated Valuation of Ecosystem Services and Trade-offs model. According to the spatial differentiation of carbon storage, the Geographical Detector model was applied to evaluate the explanatory power of natural environmental and socio-economic factors. The framework was integrated with mechanism interpretation, spatial response, and planning strategies. In addition, Morphological Spatial Pattern Analysis was used to identify ecological patches with high carbon storage. Ecological corridors were simulated using the Minimum Cumulative Resistance model, according to the resistance surface from the key landscape constraints. The spatial regulation strategies were proposed to improve the regional performance of the carbon sink. The results reveal that there was significant spatial variation in the land use and carbon storage in the Yellow River Delta over the past three decades. (1) Land use changes were primarily characterized by the conversion of wetlands and marshlands into cultivated land, aquaculture ponds, and construction land. These transitions occurred mainly in areas experiencing intensified human activities in the central and southwestern parts of the delta. Consequently, the spatial pattern of carbon storage gradually developed with relatively high values in the northeastern coastal area and lower values in the southwestern inland region, indicating the contrast between natural wetland ecosystems and developed agricultural and urban landscapes. (2) Geographical Detector results indicate that vegetation conditions and soil properties dominated the distribution of carbon storage. Vegetation coverage was represented by the Normalized Difference Vegetation Index, indicating the strong explanatory power for carbon storage patterns. Soil salinity and clay content also shared a considerable influence on the spatial differentiation of carbon storage. Socio-economic factors influencing carbon storage, including population density and gross domestic product, were attributed to the land development intensity and landscape transformation. Environmental conditions and human activities were combined to further enhance the spatial heterogeneity in the delta. (3) According to the spatial characteristics of carbon storage and the contribution rate of the driving factors, the study area was classified into four spatial regulation zones, including carbon sink core conservation, carbon sink optimization and regulation, carbon sink fragile restoration, and low-carbon intensive development zones. There was a zoning difference in the ecological importance, restoration potential, and development intensity among different areas. (4) Carbon sink areas and ecological corridors were identified after spatial connectivity analysis. Ecological patches were extracted to simulate the corridor after morphological spatial pattern analysis. The potential pathways were identified to connect these patches using the minimum cumulative resistance model. A spatial optimization pattern was characterized by “four zones and multiple corridors” using spatial zoning with the corridor network. A carbon sink structure was formed after zoning regulation and ecological connectivity. This finding can provide an approach to assess the regional carbon storage with territorial spatial planning. The spatial framework can also offer a strong reference to improve the carbon sink capacity in estuarine delta regions.