"This really is the end of one era and the start of another," Joyce said. "The jumbo has been the backbone of Qantas International for more than 40 years and we've flown almost every type that Boeing built.
"It's fitting that its retirement is going to coincide with our centenary in 2020."
He said that 747s have been in the Qantas fleet in various forms since 1971 and the future is now with the Dreamliner.
"Over the years, each new version of the 747 allowed Qantas to fly further and improve what we offered passengers. The Dreamliners are now doing the same thing.
"The 787 has better economics and a longer range, and it's already opened up new routes like Perth to London. With a larger fleet of Dreamliners, we'll be looking at destinations in the Americas, Asia, South Africa and Europe.
"By the end of 2020 we'll have farewelled the 747, finished upgrading the cabins of our A380s, and welcomed our 14th 787."
Joyce said the Dreamliner carries fewer passengers than the larger 747 (236 seats versus 364), burns approximately 20 per cent less fuel and requires less maintenance.
To date, Qantas has taken delivery of four 787-9s with four more scheduled to arrive by the end of the year. It will receive the extra six planes by late 2020.
There are currently 10 747-400s left in the fleet and these will be retired between July this year and the end of 2020. The last of Qantas' 747s was delivered by Boeing in 2013, making it 17 years old at time of retirement.
Bye bye, Queen of the Sky
Once the largest passenger plane on Earth — before the A380 took over — the number of 747s has been declining in recent years.
There's simply no demand anymore, with Boeing predicting more interest in bigger twin-engine aircraft like the 777X or its rival Airbus' A350, CNN reports.
There's not a single US carrier that still flies 747 — with Delta sending its final 747 to an Arizona "boneyard" earlier this year, and United saying goodbye in December.
"Frankly we really don't see much demand for really big aeroplanes," Boeing vice president of marketing Randy Tinseth said last June.
"There will just be a handful moving forward. Things we do for VIPs, things we do for the president, military operations, but we don't see a significant demand for passenger 747-8s or A380s.
" ... Going forward, sales of the aeroplane will be closely tied to the cargo market. Our work continues to secure additional 747-8 Freighter orders."
The 747s were the first twin-aisle, wide-body passenger planes, and were debuted by Pan Am in 1970.