In this article, the authors analyze the current state and prospects for the development of key institutions in the field of regional security in Eurasia. ASEAN-led mechanisms and the Eurasian "continental" formats, represented by the Shanghai Cooperation Organization (SCO) and the Collective Security Treaty Organization (CSTO) have been chosen as a case-study. Special focus is put on the possibility of connecting Russia with multilateral security initiatives in Eurasia in terms of promoting Russian strategic interests, as well as realizing the potential of the SCO as a structural pillar of the emerging geostrategic space - Greater Eurasia. The authors conclude that the current state of regional institutions in the field of security does not fully correspond to Russia's interests due to the institutional limitations of multilateral formats. According to the authors, the main reason why the ASEAN-led dialogue platforms on security issues are not able to realize its potential in addressing main challenges is the nature of the principles of ASEAN cooperation that hamper the process of making a collective decision. Regarding the SCO, the authors believe that the key problem in the foreseeable future may be the achievement of consensus among the participating states after the enlargement (the accession of India and Pakistan) and, as a consequence, the need to transform the institutional format to new realities. In conclusion, the authors argue that in the long-term perspective the development of the institutional environment of Greater Eurasia for the purpose of ensuring regional security should be carried out through close coordination between the SCO and other security formats - the CSTO and the ASEAN-led dialogue structures. The article has been supported by a grant of the Russian Science Foundation. Project no. 17-18-01577 «Creation of Greater Eurasia and the Development of Strategy for Bilateral Cooperation Between Russia and Regional Countries».