Securitization has been a key aspect of China’s financial development. Since the implementation of the Reform and Opening-up policy, China’s securities industry has experienced rapid development. A large number of securities firms have grown over the past 40 years, and the distribution of the branches of these firms has expanded rapidly. In this context, securities service relationships provide important insights for the study of urban networks and are strengthening links between cities. This paper aims to analyze the core-periphery structure dynamics and as well as underlying factors of the urban network in China. First, data on headquarter and branch locations of securities firms in China is analyzed using the interlocking network model to approximate the urban network, resulting in a 293×293 valued urban network. Then, using the information hinterland theory and two types of econometric models, the pooled logit and pooled probit models, the paper identifies factors underlying variations in the network status of cities. Finally, by combining the structural dynamics and underlying factors of the urban network in China, this paper proposes a preliminary core-periphery dynamic model for further discussion of the securities service relationships in the context of the urban network. Major findings include: (1) A developing core-periphery structure in China’s urban network within securities service relationships. From 2005 to 2019, the size of the core block has expanded, and the distribution of cities’ cores tends to be decentralized, which signals the emergence of a polycentric pattern in urban network structure. The spatial pattern of the core-periphery structure corresponds to current inequalities, and overall, cities located in the four major metropolises of Beijing-Tianjin area, Yangtze Delta area, Pearl Delta area and Chengdu-Chongqing area are better positioned than those in other regions. The core block consists primarily of core cities in China’s major metropolitan areas. This is a departure from the core-periphery model in the “space of places”. Connectivity distribution in cities has shown a trend consistent with Zipf’s law, which outlined a lasting hierarchical structure in the urban network. (2) Information hinterlands are shown to decisively affect cities’ network status within securities service relationships. On the one hand, the characteristics of a given city, including political rank, market potential, knowledge base, air travel accessibility and economic openness, determine whether securities firms might profitably exploit information flows. Therefore, these characteristics are key factors underlying the core-periphery dynamics in the urban network. On the other hand, information hinterland factors are regionally heterogeneous: political rank, knowledge base, transport accessibility and economic openness have greater marginal impacts on the status of cities in the central and western regions, while market potential plays a more prominent role in China’s eastern regions. The results demonstrate that a given city’s network status is rooted in its own influence or power in the “space of places”. Network development would, therefore, not lead to a reduction of spatial economic inequality but rather, reinforce it.