Abstract: In order to find out the main reasons that affect the regional economic development gap in China, accelerate the realization of balanced economic development, firstly, by defining the research scope of market integration of key variables, the level of internal market integration and external market integration after segmentation was measured. Secondly, by constructing the dynamic panel model and using the generalized moment estimation GMM method, the impact of China’s regional market integration on regional economic development gap was demonstrated. Finally, based on the research perspective of market integration, some policy suggestions were explored to narrow the regional development gap. The empirical results show that the internal market integration has a nonlinear effect on the regional economic unbalanced growth. And the external market integration process is obviously faster than the internal market integration process, and different regions due to the implementation of different economic policies, there have been different stages of economic development momentum. At the same time, due to the evolution of the national market integration process in the different stages of development, and the region economic development difference of internal structure is not the same, and interaction of internal and external market integration to the coordinated development of regional economic has differences, namely the eastern and central regions play a role of the alternative, and the eastern region effect is more obvious; And the western region has played a complementary role.

Key words: internal market integration, external market integration, regional economic disparities, system GMM