The bay on which Cygnet sits was named Port des Cygnes (Port of Swans) by French navigator Bruni D'Entrecasteaux in 1793, because he observed a large number of swans in the area.
The first European settler in the district was William Nichols in 1834. His grandson, John Wilson, established a shipbuilding business at what was now known as Port Cygnet.
In 1840 the township of Port Cygnet was surveyed. The Post Office opened on 1 January 1854. The town was known as Port Cygnet until 1895, Lovett until 1915 and then Cygnet.