BAE Systems has pledged to expand its footprint in the Hunter, pre-committing to buying 4.4 hectares at Williamtown.
Newcastle Airport said the deal for land on Astra Aerolab, the defence and aerospace precinct adjacent to the airport and RAAF base, was "a significant show of confidence".
It follows BAE signing a 34-year extension on its existing lease in the area.
Airport chief executive Dr Peter Cock said the commitment would push the precinct forward.
"The importance of this agreement cannot be overstated,'' Dr Cock said.
"As Australia's premier fast jet base, RAAF Base Williamtown is home to a vast majority of Australia's F-35 Joint Strike Fighters. BAE Systems Australia plays a key sustainment role in the Asia Pacific region for the F-35 program and as such is looking to increase its presence and resources at Williamtown.
"This new footprint will allow the development of a bespoke facility adjacent to its current site that will see a significant expansion of BAE Systems' world class local workforce.
"Their commitment to a future presence at Astra Aerolab is an important step in ensuring we continue to deliver on our promise of being uplifting by building a thriving, world leading defence and aerospace ecosystem at Williamtown."
Andrew Gresham, BAE Systems Australia's managing director of defence delivery, said the company's support for the F-35 fleet offered extensive opportunities for industry.
"Astra Aerolab will facilitate the continued development of our capabilities and resources in support of the F-35 Joint Strike Fighter," he said. "There is an exciting future ahead for Williamtown."
The Aerolab precinct spans more than 100 lots spread across 76 hectares.
The $19.66 million project, which has been funded by the state government with support from Newcastle and Port Stephens councils, is expected to deliver 5500 jobs when the site is fully developed.
