Abstract Last century witnessed the increase of metropolitan regions and much attention has been paid on them. The concept of megacity appeared during the development process of metropolitan regions. Due to the rapid urbanisation and the population explosion in China, there are three main megacities which have great influence on the national economy. In this thesis, we choose one of the main megacities - Beijing megacity, as our case and the research question is how to strengthen the polycentricity of Beijing megacity to achieve more balanced development. In order to find out the answers to the research question, the concepts of metropolitan region, megacity and polycentric megacity are discussed in the conceptual section of this thesis. The empirical section analyses the Tokyo megacity and Los Angeles megacity on purpose of finding the lessons and experiences that could be learned and applied to strengthen the polycentric characters of Beijing megacity. In the case study chapters, firstly we analyses the problems of monocentric Beijing municipality, then we suggest the approaches of being polycentric Beijing megacity where Beijing, Tianjin and Tangshan participate actively.