The construction of Chengdu-Chongqing Economic Circle is an important regional development strategy of China.It promotes the formation of domestic circulation, and the formation of domestic and international double circulation of the new pattern of development.The key to the construction of twin city economic circle is to promote the coordinated development of Chengdu-Chongqing region,optimize the regional economic layout, and form high-quality growth poles.In order to enrich the theory of regional coordinated development, this paper introduces the functionalism theory and uses the classical theory to explain the internal logic and path strategy of the coordinated development of Chengdu-Chongqing Economic Circle.The research shows that the Chengdu-Chongqing Economic Circle should take the economic and social coordination as the goal, use the ramification to start the original power, give full play to the spillover power,mobilize the initiative of the government, elites, enterprises and institutions, and build a systematic regional cooperative development organizational structure.The paper points out that the construction of Chengdu-Chongqing Economic Circle needs to go through five stages: dismantling barriers, unblocking connections, forming alliances, regional identity and deepening coordination.At the same time, Chengdu-Chongqing region needs to explore the driving force of coordinated development, maintain the balance of interests, and promote the coordinated linkage of policies,economy,society and the rule of law. With the help of functionalism theory, this paper studies the coordinated development of Chengdu-Chongqing Economic Circle, which is of reference significance to enrich the theory of regional coordinated development in China and guide the construction of Chengdu-Chongqing Economic Circle.