According to the population and economic size and interactive relationship evolution process of all the 11 cities in Guangdong-Hong Kong-Macao Greater Bay Area，we summarized the three effects of “polarization”，“trickle down” and “network” in different development stages of the core cities. At least in the stage of function spillover，the core cities held the demand for regional cooperation，and in the stage of networking，with the continuous promotion of cooperation，a new model has been formed. We constructed an explanatory framework based on the combination and evolution of three factors：spatial proximity，functional complementarity and the role of government and market，analyzed the regional cooperation model between the core cities in Guangdong-Hong Kong-Macao Greater Bay Area，and focused on the Comparison development of “The integration of Guangzhou and Buddhism” and “The integration of Shenzhen Dongguan Huizhou Hui”，in order to provide reference for the regional cooperation of other cities.