In order to explore the relationship between metazooplankton (Rotifers, Cladocera and Copepod) community structure and water environmental factors in Suzhou urban river, bimonthly quantitative collection and analysis of metazooplankton were carried out at 23 monitoring points in 8 urban areas of Suzhou City from January to November 2018 (Fig. 1), and the water environmental factors were determined. Metazooplankton were collected according to the national standard method and identified under microscope. A total of 127 species of zooplankton were identified, including 48 species of Rotifers, 41 species of Cladocera and 38 species of Copepod. The number of species in Shantang area was the highest, with 81 species, while in Western of the city the number was the lowest, with 49 species (Fig. 2). The water environmental factors were determined according to the national standards (Table 1), and it was found that there were some differences among different regions (P < 0.05). Using the formula to calculate the dominance (Y) of metazooplankton in Suzhou urban river, 24 species of annual dominant species (Y ≥ 0.02) were identified (Table 2). Using the formula to calculate the niche breadth (Bi) and niche overlap (Qik) of dominant species, it was found that the niche breadth was 0.25﹣0.84 (Table 2). According to this, the dominant species of metazooplankton in Suzhou urban river were divided into three niche groups, and the habitat heterogeneity between different areas led to a large difference in niche overlap (Fig. 3). The average annual total density of metazooplankton in each area was 124.1﹣626.4 ind/L (Fig. 4), with the highest in Western of the city and the lowest in Ganjiang area. Rotifers account for more than 85.3% of the total metazooplankton density in each area, making them an absolute dominant group. The annual total biomass of metazooplankton in each area was 0.49﹣1.12 mg/L (Fig. 5), with the highest in Western of the city and the lowest in Southern of the ancient city. The variation law of metazooplankton biomass in each area is not completely consistent with the change of density. Different habitats in different regions lead to differences in the current stock of metazooplankton. The metazooplankton community composition and environmental factors were subjected to detrended correspondence analysis (DCA), because the maximum gradient was more than 3, so the final selection canonical correspondence analysis (CCA) was selected for the constrained sequencing. Canonical correspondence analysis shows that electrical conductivity, water temperature, dissolved oxygen, transparency, chlorophyll a, total nitrogen and total phosphorus are important environmental factors affecting the metazooplankton community structure in Suzhou urban river.