Victoria state police said the woman was walking along a bay in Melbourne when she became distracted by her Facebook feed and plunged off the pier into the chilly water - but managed to hang on to her phone throughout the ordeal.
A witness called for help and police found her flailing around in the water, about 65 feet from the pier. She told police she could not swim.
The woman was taken to a hospital for treatment. Police said the woman was a foreigner but gave no more details.
"She was still out in the water lying on her back in a floating position because she told us later that she couldn't swim," Senior Constable Dean Kelly of the state water police said.
"She still had her mobile phone in her hand and initially she apologised and said sorry.
"With Facebook, or social media in general as far as we're concerned, if you're anywhere near the water just pay attention. Especially if you can't swim."