Paramedics were called to Port Noarlunga jetty just before 1.30pm following reports a woman had been bitten by a shark.
The 32-year-old suffered serious but non-life-threatening head injuries from the suspected attack, an SA Ambulance spokeswoman said.
She was rushed to the Flinders Medical Centre by road and is in a serious but stable condition.
Police said swimmers were evacuated from the water while a search was held for the shark, but it wasn’t found.
It comes after two fatal shark attacks in South Australia earlier this year.
In May, 46-year-old local teacher Simon Baccanello was killed by a shark at Walkers Rock Beach, near Elliston on the Eyre Peninsula.
Then, in October, 55-year-old Tod Gendle was killed by a 4.2-metre great white shark while surfing at Granites Beach, south of Streaky Bay on the Eyre Peninsula.
– With AAP
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