Abstract: To understand the changing laws of net fouling biological communities in the Leizhou Bay and provide a scientific basis for cage anti-fouling and green farming,the annual hanging net experiment divided into upper and down water layers carried out at the southeast wharf of Leizhou Bay from June 2020 to June 2021.The results showed that a total of 35 species of fouling organisms were detected, belonging to 11 phylums, 28 families and 35 genus.The spatial characteristics were the total number of species (29~32), Shannon-Wiener index (H', 0.985~2.010), Pielou index (J, 0.539~0.852), and Margalef index (d,0.539~2.856) in the upper and lower water layers.The abundance was higher than that in the lower water layer (8.50 ind·cm^-2), and the biomass was higher than that in the lower water layer (0.01 g·cm^-2), which showed that the fouling organisms in the upper water layer were larger in fouling and body size.The seasonal variation was characterized by the least species in winter (7 species).Using Excel and SPSS, the diversity and univariate analysis of 56 net samples were carried out respectively.The results showed that Shannon-Wiener index (H') and Margalef index (d) in winter were lower than those in other seasons, but evenly there was no difference in the Pielou index (J); compared with time accumulation, the most types of nets were attached throughout the year, then could conclude that the longer the time, the richer the species diversity.The RDA analysis showed that temperature affects the structure of the fouling biological community.The main groups of net fouling organisms in the waters of Leizhou Bay include Arthropoda, Molluscs and Chlorophyta.Spatially, there was little difference in biodiversity between upper and lower water layer.The biodiversity in spring, summer and autumn was larger than that in winter, while temperature (average contribution rate: 44.95%) and salinity (average contribution rate: 31.90%) were the main environmental factors affecting the community structurp/>