This study focused on monitoring the dynamics of bacterial communities and assessment of the influences of physicochemical parameters during a culture cycle in black carp polyculture ponds. Our results showed high variation in microbial diversity and microbial composition in the water column during the culture period. Proteobacteria, Actinobacteria, and Bacteroidetes were the most abundant phyla, while the abundances of the phyla Cyanobacteria, Firmicutes, and Bacteroidetes changed in different months. Moreover, 13 abundant genera with significant difference were found between different months. Thus, samples in different months were divided into three groups according to principal coordinate analysis (PCoA) and unweighted pair-group method (UPGMA) clustering results. RDA showed that total nitrogen (TN), total phosphorus (TP), phosphate (PO₄³⁻-P), nitrate (NO₃⁻-N), temperature (T), dissolved oxygen (DO), and pH significantly shaped the microbial community composition in different months. While Pearson correlation coefficient showed that T, SD, and pH were strongly correlated to the dominant genera. Considering some genera are potential pathogenic bacteria, we could manage the black carp pond by quickly monitoring the water temperature and SD in the future.