Abstract: In order to find out the current status of plankton and macrobenthos resources in the Heishi River Basin, Chongzhou City, Sichuan Province, a systematic survey and analysis of the resource status of plankton and macrobenthos and their community structure characteristics were carried out in October 2023 in the basin. The results of the study showed that 125 species of phytoplankton (including variants) from 47 genera in 6 phyla were identified in the Heishi River Basin, with a total mean abundance of 34.11×10⁴ ind./L and a total mean biomass of 0.324 7 mg/L. The diatom phylum had the relatively highest number of species, total mean abundance, and total mean biomass; and there were 30 species of 15 genera of phytoplankton, with a total mean abundance of 19.09 ind./L total mean biomass of 0.053 6 mg/L, of which protozoa had the highest abundance and copepods had the highest biomass, 12 orders and 27 species of macrobenthos, with a total mean abundance of 18.2 ind./m² and a total mean biomass of 3.223 7 g/m², of which aquatic insects had the highest number of species and total mean abundance and molluscs had the highest biomass. The structural characteristics of aquatic communities in the Heishi River Basin in Chongzhou City were obvious. Among them, the plankton species and resources were high, and among the phytoplankton, diatoms were absolutely dominant; in terms of macrobenthos, there were more clean-water-loving species in the upstream area, while the middle and lower reaches were dominated by species with higher pollution tolerance. The results of this study can help to better manage the fishery resources in the Heishi River Basin and develop corresponding conservation strategies.