The Vasse-Wonnerup Estuary is an estuary in the South West region of Western Australia close to the town of Busselton. The estuary is listed with DIWA. It was also recognised as a wetland of international importance under the Ramsar Convention on 7 June 1990 when an area of 1115 ha was designated Ramsar Site 484 as an important dry-season habitat for waterbirds.