This chapter on the analysis of current situation of the development of a large bay area of Guangdong，on the basis of analysis and the obstacles faced，combining the theory of regional harmonious development and Hong Kong and Macao to the bay area development planning outline，build more adequately reflect the bay area coordination development level index system，using the entropy method，total points- “method and coupling coordination degree model to evaluate a large bay area of Guangdong coordination development level in 2006-2018，the empirical analysis results show that during the period of 2006-2018，a large bay area of Guangdong overall coordination development level on the rise，but internal development not balanced，and there is a big regional differences；The average score of the four first-level indicators is highest for sustainable development potential，followed by ecological development level，social development level and economic development level. By region，Hong Kong scored the highest in the four first-level indicators，while Jiangmen scored relatively low. In addition，the Greater Bay Area of Guangdong，Hong Kong and Macao does not have a high degree of coupling coordination，and each city within it has a large room for growth. Therefore，in order to promote the coordinated development of Guangdong-Hong Kong-Macao Greater Bay Area，it is necessary to accelerate the integration of Guangdong，Hong Kong，Macao and three markets，optimize the industrial structure，accelerate the construction of infrastructure，build a joint prevention and control organization for the environment，accelerate the construction of a new pattern of opening to the outside world，and realize high-standard opening to the outside world.