HMS Cygnet was a modified Black Swan-class sloop of the Royal Navy.

She was transferred in April 1943 to the 7th Escort Group based in Greenock to support convoys threatened with attack by U-Boats in the North Atlantic.

On 8 April 1944 the Cygnet with the sloop HMS Crane sank the U-962 in the North Atlantic north-west of Cape Finisterre by depth charges.

Cygnet resumed the protection of convoys from July 1944 until the end of the war in Europe leaving or arriving from Kola Bay.

The order to leave for the Pacific was cancelled following the dropping of atomic bombs on Hiroshima and Nagasaki and the subsequent surrender of Japan.