AbstractAir connectivity is a crucial factor for economic development, especially for a free port city such as Hong Kong. This paper examines the role changes of Hong Kong in providing connectivity for the international market that originates from regional airports in Mainland China. The time-dependent earliest arrival time method is employed to assess its connectivity levels compared with other Chinese air gateways in 1998 and 2018, with measurement of three indicators: accessibility, dependency, and centrality. Empirical evidence demonstrates that extensive progress of accessibility and dependency has been presented in both Hong Kong and other Chinese gateways as for liberal arrangements after 2001, while foreign transfers are still an inescapable theme to strengthen air connections. In addition, Hong Kong retained its hub status even while deemed inferior to Beijing and Shanghai in the international market of Mainland China, especially for the Northeast and East Coastal region and air travel to Asia-Pacific, Europe, Middle East, and Africa. What is more, although Hong Kong benefited from its massive traffic generation, major air gateways would be dispersedly located across Mainland China with the rise of central China, geographical proximity effect, and differential market cultivation.