The bull shark was seen in Biggera Waters at the weekend.
Sea World staff came to its rescue, using whale-untangling tools to remove the chain from the shark’s dorsal fin.
“We did follow the shark for a fair while after we did release that chain,” Sea World head vet Dr Claire Madden said.
“I can report it was only superficial wounds.”
It’s unknown how the shark came to be entangled in the chain.