It comes after the airline ordered 12 Airbus A350-1000s to operate ultra-long-haul routes from Australia to other cities up to 20 hours in duration.
The "Project Sunrise" services will offer "market-leading" passenger comfort with flights due to start by the end of 2025 from Sydney.
Domestically, Qantas will start the renewal of its narrow-body jets as part of "Project Winton" with orders for 20 Airbus A321XLRs and 20 A220-300s as its Boeing 737s and 717s are gradually retired.
The first of these aircraft will start to arrive in late 2023, with the order including purchase right options for another 94 aircraft for delivery through to at least 2034.
Qantas said the additions to its fleet will help create 1,000 jobs as well as many career progression opportunities.
Qantas Group chief executive Alan Joyce said the new types of aircraft "make new things possible".
"That’s what makes today’s announcement so significant for the national carrier and for a country like Australia, where air travel is crucial," he continued.
"The A350 and Project Sunrise will make any city just one flight away from Australia. As you’d expect, the cabin is being specially designed for maximum comfort in all classes for long-haul flying.
"These newer aircraft and engines will reduce emissions by at least 15% if running on fossil fuels, and significantly better when run on Sustainable Aviation Fuel. Project Sunrise will be carbon neutral from day one."
