Abstract: The Lancang–Mekong Cooperation (LMC) mechanism, in which China plays a leading role, was officially launched in March 2016 as a result of China’s need for an enhanced neighbourhood diplomacy, and the development needs of the five ASEAN Mekong countries and ASEAN integration. China makes great efforts to promote LMC in order to nurture it into a “golden brand” for building a community of a shared future with the neighbouring countries and for the whole of Asia. However, in the face of challenges from within and outside of the cooperation mechanism, China has much to accomplish in building LMC as the platform to achieve its neighbourhood diplomacy goal.