[3] Unlike the rest of Hong Kong, the passenger compartments of trains operating on the Hong Kong Express Rail Link are legally defined as part of the Mainland Port Area and subject to the laws of mainland China.

[7] The government stated the objectives were to "reinforce Hong Kong's position as the transport hub in southern China and integrate Hong Kong into Mainland China's rapidly growing express rail network", and promoting cultural tourism.

[7][8] Hoping to be able to start construction of the Hong Kong section of the Express Rail Link (XRL) project before the end of 2009, the Executive Council approved the implementation on 20 October, paving the way for funding approval from the Finance Committee of the Legislative Council.

[9] The dedicated track will enable a top speed of 200 km/h;[9] the expected travel time from Kowloon to Shenzhen's Futian station is 14 minutes.

From January 2020, the line was closed owing to the COVID-19 pandemic and the border restrictions between Hong Kong and mainland China.

[16] In 2024, it was announced that the Guangzhou–Kowloon through trains operated by MTR and China Railway Guangzhou Group had been discontinued, with the General Administration of Customs stating that high-speed passenger trains have effectively met the travel needs of passengers between the mainland and Hong Kong.

The completion of the XRL HK section had been delayed on multiple occasions and continuously ran over budget, attracting criticisms from many Hong Kong protestors.