Sydney Cove is a small bay on the southern shore of Port Jackson (commonly but incorrectly called Sydney Harbour), on the coast of the state of New South Wales, Australia. Named after the British Home Secretary, Thomas Townshend, Lord Sydney, it was the site chosen by Captain Arthur Phillip on 26 January 1788 (now commemorated as Australia Day) for the British penal settlement which is now the city of Sydney.

Phillip's instructions were to establish the settlement at Botany Bay, a large bay further down the coast. Botany Bay had been discovered by Captain James Cook during his voyage of discovery in 1770, and was recommended by the eminent scientist Sir Joseph Banks, who had accompanied Cook, as a suitable site for a settlement. But Phillip discovered that Botany Bay offered neither a secure anchorage nor a reliable source of fresh water. Sydney Cove offered both of these, being serviced by a fresh water creek which was soon to be known as Tank Stream.

The Australian writers Flora Eldershaw and Marjorie Barnard (writing under their joint nom de plume M Barnard Eldershaw) wrote in Phillip of Australia (Angus and Robertson, 1938): :"The site of the settlement was Sydney Cove... It was one of the smaller inlets, chosen because it had fresh water and good anchorage for ships close into the land. The Governor's working party had cleared a camping ground beside the creek, which stole silently along through a very thick wood, the stillness of which had then for the first time since the Creation, been interrupted by the rude sound of the labourer's axe..."

Today both the creek and the wood have disappeared beneath the streets of the central business district of Sydney. The head of the cove is occupied by the Circular Quay ferry terminal. On Bennelong Point at the northern end of the eastern shore of the cove stands the Sydney Opera House. On the western shore is the historic district known as The Rocks.