The state government in New South Wales wants to change the berthing fees for cruise liners in Sydney from an hourly rate for docking to a fee per passenger.
A fee of $A18 per passenger is proposed, rising to $A30 in 2015.
The ABC reports that could see costs for some liners rise from $A3000 for an average stay to $A115,000. The price rise is the first since 1996.
The Tourism & Transport Forum says such an increase would turn Sydney into the most expensive port in the world.
Chief executive John Lee said moving to a per head charge to reflect the costs of bigger ships was logical, but the proposed fees are too high.
A fairer way of recovering costs would be to charge a third of that.
"Sydney pretty much overnight will (be) ... more expensive than New York, more expensive than Barcelona," he said.
But NSW Ports Minister Duncan Gay said the cruise ship industry can afford the new levies.