The authors studied the ecological state of the ancient lakes Yantarnoe 1 and Yantarnoe 2 in the Nadym river basin. Both lakes are subject to intense anthropogenic impact, which arose during the period of oil and gas development of the Nadym lowland and the formation of the city of Nadym. Water areas of water bodies are differentiated by the content of pollutants. The water in the lakes mainly belongs to the classes “dirty” and “polluted”, less often “clean” and “moderately polluted”. In the lakes, there is a high number of invertebrates with a low species diversity. Measures have been developed to improve the ecological state of water bodies.