A group of 11 Indonesian fishermen shipwrecked by Cyclone Ilsa have been rescued from a remote island off the Western Australian Coast.

The survivors were marooned for six days without food and water in The Rowley Shoals, about 300 kilometres west of Broome.

Australian Maritime Safety Authority said they were rescued late on Monday only after a surveillance flight spotted their makeshift camp and beached boat on a small sandy island.

Nine other fishermen remain missing after the terrifying ocean ordeal and are feared dead.

“The survivors reported that there had been two fishing vessels with 10 crew each, but one vessel had sunk in the extreme conditions of the cyclone, ” a spokeswoman said in a statement on Tuesday.

“The remaining vessel managed to rescue the only survivor before being washed ashore on Bedwell Island.”

Indonesian search and rescue authorities have told the ABC that one man survived 30 hours in the water, with only a jerry can to keep himself afloat, before floating to the island with the others.

The survivors were flown to Broome for medical care. Plans are underway for their repatriation to Indonesia.

Cyclone Ilsa tracked down the Kimberley coast before crossing the coast north-east of Port Hedland as a destructive as a category five system about midnight last Thursday.

-with AAP