China's rise signifies a gradual transformation of the international system from unipolarity to a non-unipolar world. As an organization of small and middle powers, ASEAN faces strategic uncertainties brought about by the power transition in the system. Deepening economic interdependence between ASEAN and China has amplified the economic cost for the ASEAN states to use traditional military means to deal with China s rise. Applying institutional balancing theory, this paper examines how ASEAN has adopted various institutional instruments, such as the ASEAN Regional Forum (ARF), the East Asia Summit (EAS), the Regional Comprehensive Economic Partnership (RCEP), and the ASEAN Community, to constrain and shape China s behaviour in the region in the post-Cold War era. It argues that due to globalization and economic interdependence, the power transition in the 21st century is different from the previous ones. ASEAN can potentially make a great contribution to a peaceful transformation of the international system. How to resolve the South China Sea disputes peacefully will be a critical task for both the ASEAN and Chinese leaders in the next decade or two.