Oatley is a suburb in Southern Sydney in the state of New South Wales, Australia. It is located 18 kilometres south of the Sydney central business district and is part of the St George area. Oatley lies in the local government area of Georges River Council. It lies on the northern side of the tidal estuary of the Georges River and its foreshore includes part of Oatley Bay and Lime Kiln Bay, and all of Neverfail Bay, Gungah Bay and Jewfish Bay.

Southern Sydney is the southern metropolitan area of Greater Sydney, in the state of New South Wales, Australia.