Green Square railway station is located on the Airport line in the locality of Green Square. The station is situated at a five-way intersection which is the meeting point of the four suburbs, Alexandria, Zetland, Waterloo and Beaconsfield. It is served by Sydney Trains T8 Airport & South line services.

The Airport Link is Sydney's inner-southern railway line connecting Sydney Airport to the central business district and the south-western suburbs of Sydney. With the exception of Wolli Creek, the Airport Line stations are operated by a private company, the Airport Link Company, as part of a public private partnership. The contract, which expires in 2030, allows the company to charge a surcharge on top of the normal fare. The line is served by Sydney Trains T8 Airport & South line services.