Onkaparinga River National Park is a protected area in the Australian state of South Australia located about 32 kilometres (20 mi) south of Adelaide city centre. It extends over the floodplain of the Onkaparinga River east of Main South Road.

The Onkaparinga River, known as Ngangkiparri or Ngangkiparingga in the Kaurna language, is a river located in the Southern Adelaide region in the Australian state of South Australia. Rising in the Mount Lofty Ranges, the river's estuary extends from Old Noarlunga to the river's mouth between the suburbs of Port Noarlunga and Port Noarlunga South.