The men, who are yet to be named, were swimming off the WhitSunday islands on Tuesday when they were attacked, according to their tour organiser Zigzag Whitsundays.
They were brought seven miles by boat to the mainland town of Airlie Beach where paramedics were waiting for them.
They were then flown by helicopter to a hospital in the city of Mackay in a serious by stable condition.
The attack apparently occurred while the pair were “wrestling” in the water.
The victims told the helicopter crew “they were wrestling and thrashing about in the water” in a passage between Hayman and Whitsunday Islands when they were attacked, RACQ CQ, the helicopter rescue service, said in a statement.
“An English tourist has had his foot bitten off and another has serious lacerations to his lower leg after a shark attack in the Whitsundays today,” the statement said.
The 28-year-old man lost his foot, the Mackay Base Hospital said in a statement.
A shark killed a man in November last year in a Whitsunday Island harbour where two tourists had been mauled a month earlier.
The 33-year-old victim had been diving from a paddle board while on a yacht cruise.
The spate of attacks in the Whitsundays left authorities struggling to explain an apparent escalation in danger in the internationally renowned vacation destination.
In September last year, two Australian tourists were mauled on consecutive days, one a 12-year-old girl who lost a leg.
But despite tens of millions of people visiting Australian beaches every year, shark attacks remain rare.
Additional reporting by AP
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