Raytheon UK, which already employs 145 people near Broughton, Flintshire, officially opened a new hangar.
The defence systems firm has a deal to maintain long-range RAF spy planes, which work over Syria and Iraq.
But it hopes to win contracts to provide similar aircraft to other governments.
The new Hangar 119 is equipped to completely overhaul the RAF's fleet of Sentinel surveillance aircraft - most of which were built by Raytheon.
Richard Daniel, Raytheon UK chief executive said: "Our new facility in north Wales gives us tremendous potential and will enhance our economic impact in the region, where the company has contributed since 1993.
"We have created around 50 jobs in Broughton over the past 18 months, and anticipate the need for a further 200 over the next three years depending on export opportunities."
The Welsh Government have invested Â£1m in the facility, which First Minister Carwyn Jones is officially opening later.
The UK Government announced a Â£130m deal to maintain the aircraft last autumn.
The long-range spy planes are at the frontline of surveillance against so-called Islamic State (ISIS).
The five-year contract also supports another 120 jobs at RAF Waddington in Lincolnshire, where the aircraft is based.
Welsh Secretary Alun Cairns said: "Raytheon's continued investment in north Wales is yet another strong endorsement of the confidence the company has in the skills-base and the business environment in Wales, and is further proof that this country is very much open for business."
An aircraft company could take on another 200 workers over the next three years, it has revealed.