This study uses data on the geographical distribution of financial institutions in multiple industries and applies social network analysis methods to examine Chinese financial networks. Additionally, a geographic detector model is applied to explore the factors influencing the formation of the networks’ spatial structure. The results showed that: (1) Financial networks were found to be characterized by a “core-edge” structure, with core cities located mainly in the eastern region and peripheral cities located mainly in the central and western regions, while a decreasing degree of network spatial differentiation was found. In addition, the existence of spatial directionality was identified in the networks’ spatial structure. The development of financial networks in the central and western regions and peripheral cities was found to be dependent on a “radiation” process arising from the eastern regions and core cities, in which the “trickle-down effect” on the extra-territorial cities is fully exploited. In the eastern region, infrastructure is well developed and the business environment and other related conditions are relatively good due to the region’s high level of economic development and the presence of many financial enterprise headquarters. (2) The factors that influence the development of financial networks differ across the country, eastern and central and western regions, and core and peripheral cities, being closely related to the respective economic development level, market potential, key resources, locational conditions, and operating costs. The factors affecting the development of financial networks are more diverse and the interactions between the influencing factors are more balanced in the central and western regions and peripheral cities than those in the eastern region and core cities. (3) Merit selection, path dependence, and network proximity are the inherent mechanisms followed in the formation of the networks’ spatial structure; merit selection determines the spatial directionality of financial markets, while path dependency drives the formation of the networks’ spatial structure and determines “core-edge” characteristics. In addition, the stronger the financial linkages between cities, the greater the capability of cities with higher network accessibility to utilize network resources. The study contributes to the theory of “space flows” and, in the context of increasing economic and financial integration, points to the need for governments at all levels to strengthen financial cooperation between cities, and to do so at a larger scale. While promoting financial and economic development, attention should be paid to unbalanced spatial structures, with particular recognition of the importance of promoting the coordinated development of cities in the central and western regions and of further leveraging the role of core cities as “radiation” drivers. Through its examination of the characteristics of the spatial structure of China’s financial network and its influencing factors, the study provides both policy recommendations regarding the optimization of financial resources allocation and a scientific basis for the formulation of policies aimed at promoting coordinated intercity development.