The compact urban construction is a new way to avoid the disorderly spread of the city, improve the quality of urban development and realize the efficient use of land resources. Therefore, it is essential to coordinate the relationship between urban compactness and urbanization level. Based on this, this paper takes 30 provincial capital cities and municipalities directly under the Central Government as the research object, and comprehensively uses the entropy method and capacity coupling coefficient model to measure the comprehensive level of provincial capital compactness and urbanization, and analyzes the coupling and coordination relationship between them. The results show that: (1) The compactness of China's provincial capitals continued to increase between 2006 and 2016. The compactness of the eastern provincial capitals was slightly higher than that of the central and western cities, showing the characteristics of the current situation of the east, the middle, and the west. (2) The city of compactness is gradually decreasing, and the number of the cities with medium and low compactness is increasing. (3) The relationship between compactness and urbanization of most provincial capital cities in China is mainly on the verge of coordination, and the overall transition changes from disordered state to coordinated state.