By Agency- A wedding party was having photos taken on Glenelg jetty when someone spotted the 55-year-old woman bobbing in the water.
A group including the bride and groom went to the woman's aid.
Shane Daw of Surf Life Saving South Australia said the bridal party members performed CPR with the help of surf life saving volunteers for about five minutes until the woman resumed breathing and regained consciousness.
"She's very lucky (one) that the bridal party was there and they acted quickly and got her to the shallows and then also very lucky that there was surf life savers there who were able to assist," he said.
"They did a fantastic job."
The woman pulled from the sea has suspected spinal injuries.
Mr Daw said she fell off the jetty into shallow water.
He said it was not the first time a group in formal wear had gone into the sea along the Adelaide coast.
"We've had a range of incidents over the years where we've had ... people where they've had christenings, there's been bridal parties," he said.