Introduction. The article discusses the measures taken in Russia and other Caspian littoral states to protect the environment of the Caspian Sea. Theoretical analysis. The author explores measures to develop an eco-network approach to the protection of water and biological resources of the Caspian Sea, problems of biodiversity conservation, the importance of protecting the Caspian ecosystems in the strategy of transition to sustainable development, as well as environmental threats due to sea level changes. Results.