The article considers the key factors that affect the stability of the Antarctic Treaty System (ATS), erode its basic norms and provisions, lead to strengthening of political and legal contradictions between countries and, in general, to a prospective strengthening of interstate conflicts. Among those factors are the attempts of some claimant states to form maritime zones of sovereignty, sovereign rights and jurisdiction in the Antarctic waters and the process of defining the outer limits of the continental shelf within the framework of the Commission on the Limits of the Continental Shelf initiated by them. The author shows how justifying their actions with references to the rights and powers granted to them under modern international maritime law, and above all the 1982 UN Convention on the Law of the Sea, leads to an imbalance of the entire System. The unresolved questions concerning the applicability of the concept of common heritage of mankind (CCH) to the Antarctic, the legality of the formation of maritime zones around the sub-Antarctic islands and restrictions on the exercise of national jurisdiction on the continent itself increase pressure on the sustainability of the established legal regime. It is in the interests of the Russian Federation not to allow the complete destruction of the established system of governance, and if it is inevitable, to be ready to pursue an active policy to defend its national interests.