As traditional geographical distances diminish, new patterns of regional spatial configuration continuously emerge and develop, with the dominance of flow space shaping the new landscape of regional spatial networks. From the viewpoint of passenger flows, and with the help of the social network analysis method, the present paper constructed a comprehensive passenger flow matrix based on passenger frequency data. It analyzed the characteristics of the passenger transport network of the Pearl River Delta Urban Agglomeration from three aspects, namely network nodes, connection flow lines, and the overall network. and then explored its influencing factors. The results showed that: (1) From the point of network nodes, the Pearl River Delta urban agglomeration passenger transportation network shows the characteristics of multiple levels and regional differentiation as a whole, plays a leading role as the first level of Guangzhou. (2) From the point of connection flow lines, passenger flows between cities are led by Guangzhou and Shenzhen, which plays a core leading role in their hinterland. The connection between cities is strong along the axis from northwest to southeast along the Pearl River. (3) From the perspective of the overall network, its development level is relatively high in the Pearl River Delta Urban Agglomeration, and the network centralization degree is relatively high as well. (4) From the perspective of influencing factors, policy and natural factors will have an impact on passenger flow. Through quantitative analysis of economic and social factors, it is found that R&D input, GDP, fixed asset investment and urbanization rate show a positive impact on passenger network, while resident population and foreign direct investment show a negative impact on passenger network. [ABSTRACT FROM AUTHOR]