Abstract: In order to understand the status of fish community in Tangpu Reservoir of Zhejiang Province of China and its key influencing factors, fishes were seasonally collected from 6 stations of this reservoir from October 2020 to October 2021, using multi-mesh gillnets, traps, and trammel nets. Correspondingly, environmental parameters were also measured. Using those data, the structural features of fish assemblage, their temporal and spatial distribution pattern and relationship with environmental factors were analyzed. A total of 41 species of fish belonging to 3 orders were collected, with Cypriniformes having the most species number (87.80%) and 4 dominant species, including bighead carp (Hypophthalmichthys nobilis), Hemiculter bleekeri, sharpbelly (Hemiculter leucisculus), silver carp (Aristichthys nobilis). Sedentary fish (92.68%), omnivores (60.98%), and epipelagic fish (48.79%) dominated in ecological types, feeding habit and habitat types, respectively. All the fish species composition, number per unit effort (NPUE), biomass per unit effor (BPUE) differed seasonally and horizontally spatially, and species number (SN) differed horizontally spatially. The catches classified into 3 clusters including S. wolterstorffi cluster, H. bleekeri cluster, and sharpbelly clulster. NPUE, BPUE and SN had the decreasing trend from middle reaches to lower reaches, the former two parameters were significantly higher in spring and summer than those in autumn and winter, but there were significant interaction effects of seasons and stations on the above 3 parameters. The fish species composition, NPUE, BPUE, and SN significantly differed vertically, and the latter 3 parameters were influenced by the interaction effect of water layers and seasons. In terms of NPUE, BPUE and SN, fishes concentrated in the surface layers in spring, summer and autumn with significantly vertical differences between water layers each season, and in the lower water layer in winter with no significant difference between water layers. NPUE and BPUE significantly correlated with chlorophyll a (Chl.a), total phosphorus, pH and/or total nitrogen (TN). Redundancy analysis showed that water temperature, pH, Chl.a and TN were the key environmental factors influencing the spatio-temporal distribution of the fish species in the reservoir. This study suggested that it's not unpromising for the fish status in Tangpu Reservoir from the perspective of function diversity despite the high species diversity, the explanation of environmental indicators of primary productivity to spatio-temporal distribution of fish assemblage is disturbed by anthropogenic factors such as fishing, and enhangcement and release, the fish vertical distribution pattern vary with season.