An assessment is given for the contemporary state of zooplankton community in the waters of the upper reaches of the Kenti River system under the conditions of long-term potash-sulfate industrial pollution. This article presents a number of structural indicators of the zooplankton community that show simplification in the structure of species diversity and its reduction, as well as the disappearance of a number of systematic groups. It is noted that the number of zooplankton taxa increases with distance from the source of pollution (Kostomukshskoe and Kento lakes), and the average quantitative indicators also increase in this case. A comparison with the results that were previously obtained for the reservoirs of the studied environment has been carried out.