This paper reports the freshwater zooplankton fauna in Zhongshan City. Study materials were collected in June, July and December 2005. Totally, 317 species of zooplankton, belonging to 129 genera, 92 families, 38 orders were obtained from Zhongshan City, of which 263 species (83% of the zooplankton species number) belong to 102 genera in Protozoa, while 37 species (12%) belong to 19 genera in Rotifera. Only 7 species of Cladocera and 10 species of Copepoda were found, which were 2% and 3% of the zooplankton species number, respectively. The zooplankton species number was 11-168 per sample station with the lowest species number (11) found in Hongqili and the maximum species number (168) found in Xiaoyao Vale. This investigation showed that Zhongshan City had abundant freshwater zooplankton species. The number of zooplankton species showed a close relationship with the trophic status of the sampling stations, the cleaner the water, and the more the species.