Benger Swamp is a wetland located on the Swan Coastal Plain, in south-west Western Australia. The wetland is situated 2 kilometres (1.2 mi) west of Benger, 14 kilometres (8.7 mi) east of the coastal town of Binningup, 12 kilometres (7.5 mi) south-west of Harvey, and 155 kilometres (96 mi) south of Perth. Some 89% of the swamp is protected within the Benger Swamp Nature Reserve, while the remaining 11%, mainly in the northern part, is privately owned. It is a seasonally important site for waterbirds and is classified by BirdLife International as an Important Bird Area, with special regard to the conservation of freckled ducks and Australasian bitterns. Water levels in the swamp are controlled artificially and are managed both for waterbird conservation and for farming.