Abstract: In the report, the net trawling method was used to investigate the community structure characteristics, spatial and temporal distribution characteristics of plankton in the Huweiling sea area in 2017. A total of 65 species of phytoplankton were found, in which 41 species of diatoms were identified. There are 21 species of zooplankton were found, including 7 species of copepods. In summer, the phytoplankton cell density and zooplankton density were highest. The dominant species of phytoplankton in the whole year were diatoms, with 15 species; the dominant species of zooplankton were copepods, with 5 species. In autumn, the dominant degree of the small ring algae was 0.60; in summer, the dominance of the root-loaded bollworm was 0.57. The plankton uniformity index was positively correlated with the diversity index, and the local plankton community structure was relatively stable. According to the diversity index pollution assessment, the sea area was under the medium pollution condition.