South bank of the Parramatta River

Homebush Bay is a bay on the South bank of the Parramatta River, in the inner west of Sydney, in the state of New South Wales, Australia. The name is also used to refer to an area to the west and south of the bay itself, which was formerly an official suburb of Sydney, which has now become the suburbs of Sydney Olympic Park, Wentworth Point and part of the neighbouring suburb of Lidcombe. Homebush Bay is located 16 kilometres (9.9 mi) west of the Sydney central business district, in the local government area of City of Auburn. Homebush and Homebush West are separate suburbs.

The bay has natural and artificial shoreline on the southern side of the Parramatta River between the former suburb of Homebush Bay and the suburb of Rhodes. The bay was contaminated with dioxin and other chemicals by Union Carbide group which led to commercial fishing bans in most of Sydney Harbour and health advisories about limiting the quantity of fish eaten from the Parramattta River. Fishing is prohibited in Homebush Bay for health reasons. Other contamination includes phthalates, lead, polycyclic aromatic hydrocarbons, DDT and heavy metals. The eastern shore of the bay was remediated starting in 2008 to remove about 75% of the dioxin from the bay. Remediation was completed in mid-2010.