The Ord River floodplain is the floodplain of the lower Ord River in the Shire of Wyndham-East Kimberley, in the Kimberley region of northern Western Australia. It lies within the Victoria Bonaparte IBRA bioregion and contains river, seasonal creek, tidal mudflat and floodplain wetlands, with extensive stands of mangroves, that support saltwater crocodiles and many waterbirds. It is recognised as an internationally important wetland area, with 1,384 km2 of it designated on 7 June 1990 as Ramsar Site 477 under the Ramsar Convention on Wetlands.
The site lies about 8 km east of the town of Wyndham, extending from 14°51′S 128°12′E / 14.850°S 128.200°E to 15°46′S 128°33′E / 15.767°S 128.550°E. It comprises the Ord River and Parry Lagoons nature reserves, with some additional land. It lies downstream of two large impoundments on the Ord River, Lakes Argyle and Kununurra, which have had a major impact on the river’s hydrology through changing its flow pattern so that there are now constant flows through the dry season. In effect, the lower Ord has been transformed through flow regulation at the dams from a ‘dry tropics’ to a ‘wet tropics’ river.