This paper analyzes the development of urban system in the Guangdong-Hong Kong-Macao Greater Bay Area. We find that its ambition faces four major challenges. First，the issue of internal industry homogeneity in the Greater Bay Area has yet to be resolved. Second，the integration of the entire industrial chain of the “two districts and nine cities” has not yet been completed. Third，the linkage mechanism of factors in the Greater Bay Area has yet to be optimized. Fourth，the positioning of the urban structure within the Greater Bay Area remains to be clarified. This paper then establishes a quantitative measurement model to deepen the understanding of the current urban system. To address the problems，we puts forward the strategic thinking of “one principle，three goals，seven policies” for the construction of the urban division of labor system in the Guangdong-Hong Kong-Macao Greater Bay Area. One principle refers to the “Guangdong-Hong Kong-Macao Greater Bay Area Development Plan Outline” as a strategic principle to guide the overall situation. The three goals are to promote the differentiated development of industries，the efficient and convenient flow of production factors，and the precise positioning of urban functions. The seven policies refer to the construction of a core support system，including a differentiated production system，market integration，major cooperation platforms，new advantages in international cooperation，multi-circle and multi-core Bay Area pattern，infrastructureinterconnection，and a high-quality living circle.