The profound transformations at the beginning of the 21 century, characterized by political changes and the diversification of geostrategic interests, significantly influence the evolution of the international security system. The cuttingedge events in Ukraine and Syria show that it has a significant change, including the trends of strategic reconfiguration of partnerships between different international security organizations, depending on the interests and security objectives of the main actor. Also the major threat to security is terrorism. Under the international security system, international security organizations are the most complex forms of international government cooperation. International organizations have become an important element of the in-ternational security system, especially after the Second World War, when their number began to rise considerably. Globally, the number of international orga-nizations is particularly high, so it is difficult to determine the specific role which they play.