>This study is an institutional analysis that aims at answering the questions：What are the underlying rules and principles of the existing structure of ASEM？What will be the impact of the operating of the institution？What do these results imply for the future relations of the two regions i.e. on ASEM and the EU？The institutional structure of ASEM is based on four main principles：（1） promoting regional integration，（2） enhancing multilateral cooperation inside and outside ASEM，（3） decentralized transnational cooperation and the promotion of issue-specific dialogue，and （4） all activities，dialogues and discussions should be based on the free will to cooperate by the members. The paper argues that these principles and the relating norms and procedures have supported the consolidation of multilateral structure in East Asia as well as the promotion of knowledge-based policy discussion. But the ASEM process has not brought about a partnership among equals；rather it put the European members in an advantageous position vis-à-vis the Asian partners. The reason is that Europeans are well-coordinated，able to mobilize more resource and equipped with relevant expertise.