Abstract: To understand the characteristics of zooplankton community structure in Baiyangdian Wetland, 8 sampling points will be set up of 2021 in Baiyangdian Wetland, and the biodiversity index will be used to evaluate the water quality. The results showed that114 species of zooplankton and zooplankton were identified in Baiyangdian Wetland, including 22 species of protozoa, 61 species of rotifers, 17 species of cladocera and 14 species of copepods. The density of zooplankton is 52.8～7542 ind/L. The main dominant species are Polyarthra trigla and Strobilidum velox. The mean value of zooplankton diversity index H ’in Baiyangdian Wetland is 2.15,and the mean value J is 0.49. The assessment results show that the water quality of Baiyangdian Wetland is in a medium pollution level as a whole.