A woman attacked by a two-metre long crocodile in Western Australia has been discharged from hospital after being treated for lacerations and puncture wounds.

The reptile bit down on Tara Hawkes' leg whilst she was working on a luxury tourist boat in the Kimberly region.

After a swim in a remote freshwater pool, the 23-year-old went to climb back on board the vessel, True North.

A crocodile that had not been spotted by the crew swam out of the waist-deep water and clamped down her on the thigh.

Pulled to safety by a passenger, Hawkes was airlifted to Derby hospital where she was given stitches.

Peter Trembath of North Star Cruises, the company that operates the ship, said it wasn't clear whether the animal had been a big freshwater crocodile or a small saltwater crocodile

"Freshies don't normally bite unless you step on them or if you corner them, which could have happened as she stepped out of the water," he told The Sydney morning Herald.

The boat is to continue on its "adventure cruise". The victim's family has flown out to be by her side during her recovery.