Since the end of the Cold War, China and Russia have restored and developed their cooperative relationship, which someone described as a new “brotherhood.” Xi Jinping and Vladimir Putin evaluated that the two countries have developed the highest level of cooperative partnership with regard to their bilateral relations in history, and they have shown common position and shared interests in international issues including respect for national sovereignty, cultural diversity, limited international intervention, and multipolar world order. Today’s world is often described as the unipolar order where the only superpower US plays the leading role who predispose international agendas and institutional framework. However, even under the unipolar world, the US global hegemony is not omnipotent, and it needs cooperation and participation of major powers in order to address various international issues, including traditional international security and emerging issues such as terrorism, resources, and climate change. Therefore, China and Russia, as the responsible major powers in international politics, are required to work together with the US and other great powers to meet the challenges that the world is facing today. This dissertation criticizes the dichotomy which understands the Sino-Russian rapprochement as the anti-liberal coalition, because the argument of the “New Cold War” does not explain the real aspects of competition and cooperation between China and Russia. In addition, preceding researches on the Sino-Russian relations are mainly focused on conflicting and compromising interests of the two powers, which is not based on a concrete and coherent theoretical framework of international relations. This dissertation tries to understand what are the national interests of the two powers for their security and prosperity and how each of them is endeavoring to achieve the policy goals, with the framework of geopolitics based on Nicolas J. Spykman’s theory. Therefore, rising China is pursuing the dominant status in East Asia through strategic conversion to build sea power in East and South China Sea, and returning Russia is reestablishing its leadership in Eurasian region by keeping guard over its traditional sphere of influence, both of which are conflicting with the US foreign policy goals on the rimland of the Euro-Asian landmass as the deterrer to keep any power from rising as a hegemony. The geopolitical analysis about the Sino-Russian relations gives a coherent and systematic framework to understand the conflicting and competing interest between the two neighboring powers and their strategic choice to compromise and cooperate to respond to the pressure coming through the rimland by the US and its alliance system.