The Australian flag carrier's boss, Alan Joyce, said the move would be "a necessity" when vaccines are available.
"I think that's going to be a common thing talking to my colleagues in other airlines around the globe," he said.
Australia shut down its international borders early in the pandemic and required those returning to quarantine.
The country has more recently relied on lockdowns, widespread testing and aggressive contact tracing to push daily infections nationwide close to zero.
In an interview with Australia's Nine Network on Monday, Mr Joyce said Qantas was looking at ways of changing its terms and conditions for international travellers as the industry, which has been hit hard by travel restrictions, looks at ways of moving forward.
"We will ask people to have a vaccination before they can get on the aircraft... for international visitors coming out and people leaving the country we think that's a necessity," he told the broadcaster.
"There are always exemptions for any vaccine on medical grounds, but that should be the only basis," he told radio station 3AW.
That same month, Qantas reported an annual loss of almost A$2bn because of the impact of the coronavirus pandemic.
Joyce said at the time that trading conditions were the worst in the airline's 100-year history and that "the impact of Covid on all airlines is clear - it's devastating".
On Monday, the Australian state of New South Wales (NSW) reopened its border with neighbouring Victoria for the first time since infections soared in Victoria's state capital, Melbourne, in July.
Flights between the city and the NSW capital Sydney - normally one of the world's busiest routes - had been cancelled.
Arriving in Sydney on a Qantas flight for the first time in months, passengers were greeted by people at the terminal holding up signs that read "welcome back".
More than 20 additional flights were scheduled between the two states on Monday.
"Today is the day I get to meet my four-month-old grandson for the first time," one passenger told the BBC.
Australia has recorded about 900 coronavirus-related deaths and almost 28,000 infections in total.