The article contains analysis of nuclear environmental problems of the Arctic region under the International Law. It seems important to further develop cooperation to strengthen the international legal framework for nuclear and environmental security in the region, and to improve the Russian national legislation. Such cooperation should be aimed, inter alia, at creating a regional treaty mechanism for responding to potential nuclear accidents by concluding an appropriate intergovernmental agreement on coordination of cooperation under the Conventions on Early Warning Notification and on Assistance in the Case of a Nuclear Accident or Radiological Emergency. Russia is the only state in the world that owns and operates a civilian nuclear icebreaker’s fleet on the Northern Sea Route. In the coming years the first floating nuclear power plant will start operating in the Chukotka Peninsula. In case of its export abroad, it will be required to create additional international legal instruments. Russia has ratified the 1963 Vienna Convention on Civil Liability for Nuclear Damage but has not yet adopted legislation on its financial implementation. It is required to adopt such a law as well as to accede to the revised 1997 Vienna Convention. Nuclear-ecological problems in connection with the elimination of the “nuclear legacy” of the Cold War are still on top of the agenda. That includes the fate of the radioactive stuffs and waste flooded in the Arctic seas. The main conclusion of the article is that the existing international legal base is ipso facto  sufficient for the continued solution of Arctic nuclear ecological problems. Additional focused efforts of all interested Arctic partners are required.