The Bohai Sea, a semi-enclosed marginal sea, hosts a diverse array of bacterial communities that play pivotal roles in marine biogeochemical cycles. However, understanding of bacterial communities remains fragmented in the Bohai Sea, with unclear links between environmental factors and key species, and limited insights into the roles of environment and space in shaping the bacterial communities. In this study, we compiled a series of data, and investigated how spatial and environmental factors influence the region's distribution, assembly, and function of bacterial communities using high-throughput sequencing and statistical analyses. The results revealed that the bacterial communities in the Bohai Sea exhibited a high heterogeneity of spatial and environmental factors. Major drivers of community assembly included geographic location, nutrient availability (NO