Oxford Economics published the forecast after assessing the impact of the £110m investment to redevelop the airport by 2020.
The report, commissioned by the airport and Luton Borough Council, predicted that LLA's contribution to the national economy will jump by 77% from £1.3bn in 2013 to £2.3bn by 2030.
The number of jobs supported by LLA is also set to rise by 2030, up from 27,200 today to 37,700. Some 3,700 new jobs will be created at the airport itself over the same period.
Expansion work at the airport includes i ncreasing the capacity of the runway, redesigning the terminal building and i mproving the main access road.
This will increase capacity from 12 million to 18 million passengers per year.
Airport chief executive, Nick Barton, said: "This report vividly illustrates the economic benefits that LLA brings to the local and regional economy.
"As we deliver on our ambitious £110m plans to transform the airport, we will be working hard to ensure that our region and local communities reap the maximum benefit and share in our success."
The Davies Commission report into UK aviation capacity, which recommended the building of a third runway at Heathrow, said airports such as Luton play a "crucial national role".
Some 12 million passengers used the airport in the past 12 months, and there was a 21.5% increase in the figure for October compared with the same month last year.