The South Asian airlines would invest an estimated $240 billion between 2013 and 2032, increasing their fleet to over 2,060 from the current 450, Vice President for market at Boeing Commercial Airplanes Randy Tinseth said.
Comparatively, airlines in China were expected to add 5,500 new planes and those in Southeast Asia 3,000.
Overall, Boeing has forecast $1.9 trillion investment on 12,820 new aircraft over the 20-year period in Asia Pacific, representing 36 per cent of the world's new airplane deliveries.
"Asia Pacific economies and passenger traffic continue to exhibit strong growth," Tinseth told reporters ahead of the opening of the Singapore Airshow from tomorrow.
"Over the next 20 years, nearly half of the world's air traffic growth will be driven by travel to, from or within the region. The Asia Pacific fleet will nearly triple - from 5,090 airplanes in 2012 to 14,750 in 2032 - to support the increased demand."
Boeing's data projects that passenger airlines in the region would rely primarily on single-aisle airplanes such as the Next-Generation 737 and the 737 MAX, a new-engine variant of the market-leading 737, to connect passengers.
Single-aisle airplanes would represent 69 per cent of the new airplanes in the region.
"New low-cost carriers and demand for intra-Asia travel have fueled the substantial increase in single-aisle airplanes," said Tinseth.
"Fuel-efficient airplanes like the Next-Generation 737 and 737 MAX help the growing number of low-cost carriers operate more efficiently and provide affordable fares to the emerging middle class," he added.
For long-haul traffic, Boeing forecast twin-aisle planes such as the 747-8 Intercontinental, 777 and the 787 Dreamliner will account for 28 per cent of new airplane deliveries.
Boeing's recently launched 787-10 and 777X will also support the demand for fuel-efficient twin-aisle airplanes in the region.
Singapore Airlines has already ordered 30 787-10s helping launch the programme at the 2013 Paris Air Show and Cathay Pacific recently ordered 21 777-9X airplanes, he said.