The A380 fleet will remain grounded "until we are confident that Qantas safety requirements have been met," CEO Alan Joyce said in a statement.
The flight from Singapore to Sydney, Australia, experienced engine problems not long after takeoff and returned to Singapore. There were 440 passengers and 26 crew on board.
There were no injuries.
Still, The Associated Press cited a passenger who claimed she heard bangs and saw flames from her windows.
"There was flames - yellow flames came out, and debris came off. You could see black things shooting through the smoke, like bits of debris," Rosemary Hegardy, 60, told the AP.
The AP also cited media reports that debris from the flight had fallen on the Indonesian island of Batam.
This is not the first flight problem that Qantas has experienced this year. In March, a Qantas Boeing 747 flying from Sydney to Singapore was forced to return to Sydney after experiencing engine problems, The New York Times said. Also in March, a locked brake caused an A380's tire to blow out as it landed in Sydney.
In August, the airline reported a "catastrophic failure" in an engine of 747 flying from San Francisco to Sydney.