Construction of dams on rivers can lead to changes in water flow and nutrient cycling due to impediments to the flow of basic nutrients. The hypothesis that the division of fish into guilds of benthic, demersal and pelagic would in a man-made lake explain the variation in the community structure was tested. The structure of vertical fish communities was described using two isometric log-ratio variables. The first variable was found to reflect the ratio of benthopelagic and demersal fish species, while the second indicated the proportion of pelagic to other fish species. The canonical correspondence analysis on these variables explained 6.4% of the observed community variations. The analysis axes reflected the variability in the fish community structure, which depends on the vertical preference of fish. During the study period in the lake ecosystem, the importance of benthopelagic guild was decreasing which was followed by a decrease in the abundance and diversity of the fish community. The lake ecosystems are located at different distances from the Dnipro River bed, and this pattern appeared to be stronger as the distance became greater. The observed temporal changes in the ecological guilds structure of the fish community were due to eutrophication and oxygen deficiency.