The Gawler River is a river located in the Adelaide Plains district of the Mid North region in the Australian state of South Australia.

The district surrounding the river produces cereal crops and sheep for both meat and wool, as well as market gardens, almond orchards and vineyards.

Formed by the confluence of the North Para and South Para Rivers in the town of Gawler, the river flows generally west onto the Adelaide Plains. The mouth is in the Adelaide International Bird Sanctuary National Park—Winaityinaityi Pangkara, which consists primarily of mangroves in the tidal flats as the river empties into Gulf St Vincent. The outflow represents the boundary between the suburbs of Port Gawler on the northern bank and Buckland Park on the southern bank. The river descends 50 metres (160 ft) over its 41-kilometre (25 mi) course.

The Angle Vale Bridge, located over the river on Heaslip Road in Angle Vale, was a laminated timber deck arch bridge built in 1876. It was the only surviving bridge of its type in Australia. The bridge collapsed in 2023, due to heavy rainfall.

The Gawler is subject to periodic flood events and the cause of occasional flash flooding (during 1:10 to 1:50 year flood events). Major overtopping in large floods occurs along much of the river length. Significant flooding commences within Gawler township from both the North and South Para Rivers.

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  Angle Vale Bridge
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  September 2010
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  September 2016

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  Heaslip Road Bridge
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  September 2016

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September 2016

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• Rivers of South Australia