Abstract:Guangdong-Hong Kong-Macao Greater Bay Area is constructing an international science and technology innovation center. This is a science and technology innovation community where the cities are closly related. The academic circle lacks the comprehensive and in-depth comparative analysis about the 11 cities in the Greater Bay Area. Taking GDDM as the theoretical framework, this paper constructs the index system of evaluation of the competitive advantage of cities, and uses the display indices comprehensive evaluation method and multi-factor comprehensive evaluation method to deeply scan the 11 cities in the Greater Bay Area in a panoramic view. The outcome shows that each city has unique core advantages and can develop in synergy. Urban diamonds are connected to each other, which make a diamond chain in the Greater Bay Area.