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.

The Mount Lofty Ranges are a range of mountains in the Australian state of South Australia which for a small part of its length borders the east of Adelaide. The part of the range in the vicinity of Adelaide is called the Adelaide Hills and defines the eastern border of the Adelaide Plains.