Since the reform and opening up，the rapid economic development and the one-way flow of various production factors have gradually widened the gap among the four sub-regions in Guangdong，including the Pearl River Delta and the east and northwest of Guangdong. The unbalanced and inadequate regional development has become a problem that must be faced up to in the high-quality development of Guangdong. Firstly，the process of regional coordinated development in Guangdong Province was analyzed，according to the strategic deployment of “one core，one belt and one area” proposed by Guangdong provincial Party committee based on the new spatial governance thinking since 2018，The index system was constructed to measure the coordinated development of the three regions in Guangdong Province from the aspects of basic public services，people’s living standards，and transportation accessibility. The results show that，since 2016，the overall regional coordination degree of Guangdong has improved，which is mainly manifested in the decline of the “polarization and storage” role of the “one core” region，the strengthening of the spillover effect of development factors，and the improvement of the regional coordination degree of the “one belt”（7 cities in eastern and western Guangdong）and “one zone” regions. Finally，we puts forward the development ideas and key points of the three regions in Guangdong from the perspective of functional integration.